<s>
In	O
computing	O
,	O
cross-platform	B-Operating_System
software	I-Operating_System
(	O
also	O
called	O
multi-platform	B-Operating_System
software	O
,	O
platform-agnostic	B-Operating_System
software	O
,	O
or	O
platform-independent	B-Operating_System
software	O
)	O
is	O
computer	B-Application
software	I-Application
that	O
is	O
designed	O
to	O
work	O
in	O
several	O
computing	B-Device
platforms	I-Device
.	O
</s>
<s>
Some	O
cross-platform	B-Operating_System
software	I-Operating_System
requires	O
a	O
separate	O
build	O
for	O
each	O
platform	O
,	O
but	O
some	O
can	O
be	O
directly	O
run	O
on	O
any	O
platform	O
without	O
special	O
preparation	O
,	O
being	O
written	O
in	O
an	O
interpreted	B-Application
language	I-Application
or	O
compiled	B-Language
to	O
portable	O
bytecode	O
for	O
which	O
the	O
interpreters	B-Application
or	O
run-time	O
packages	O
are	O
common	O
or	O
standard	O
components	O
of	O
all	O
supported	O
platforms	B-Device
.	O
</s>
<s>
For	O
example	O
,	O
a	O
cross-platform	B-Operating_System
application	B-Application
may	O
run	O
on	O
Microsoft	B-Application
Windows	I-Application
,	O
Linux	B-Application
,	O
and	O
macOS	B-Application
.	O
</s>
<s>
Cross-platform	B-Operating_System
software	I-Operating_System
may	O
run	O
on	O
many	O
platforms	B-Device
,	O
or	O
as	O
few	O
as	O
two	O
.	O
</s>
<s>
Some	O
frameworks	O
for	O
cross-platform	B-Operating_System
development	O
are	O
Codename	B-Language
One	I-Language
,	O
Kivy	B-Language
,	O
Qt	B-Language
,	O
Flutter	B-Application
,	O
NativeScript	B-Language
,	O
Xamarin	B-Application
,	O
Phonegap	B-Protocol
,	O
Ionic	B-General_Concept
,	O
and	O
React	B-Application
Native	I-Application
.	O
</s>
<s>
Platform	O
can	O
refer	O
to	O
the	O
type	O
of	O
processor	O
(	O
CPU	O
)	O
or	O
other	O
hardware	O
on	O
which	O
an	O
operating	B-General_Concept
system	I-General_Concept
(	O
OS	O
)	O
or	O
application	B-Application
runs	O
,	O
the	O
type	O
of	O
OS	O
,	O
or	O
a	O
combination	O
of	O
the	O
two	O
.	O
</s>
<s>
An	O
example	O
of	O
a	O
common	O
platform	O
is	O
the	O
Microsoft	B-Application
Windows	I-Application
OS	I-Application
running	O
on	O
the	O
x86	B-Operating_System
architecture	I-Operating_System
.	O
</s>
<s>
Other	O
well-known	O
desktop	O
platforms	B-Device
are	O
Linux/Unix	O
and	O
macOS	B-Application
-	O
both	O
of	O
which	O
are	O
themselves	O
cross-platform	B-Operating_System
.	O
</s>
<s>
There	O
are	O
,	O
however	O
,	O
many	O
devices	O
such	O
as	O
smartphones	B-Operating_System
that	O
are	O
also	O
platforms	B-Device
.	O
</s>
<s>
Applications	O
can	O
be	O
written	O
to	O
depend	O
on	O
the	O
features	O
of	O
a	O
particular	O
platform	O
—	O
either	O
the	O
hardware	O
,	O
OS	O
,	O
or	O
virtual	B-Architecture
machine	I-Architecture
(	O
VM	O
)	O
it	O
runs	O
on	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
Java	B-Device
platform	I-Device
is	O
a	O
common	O
VM	O
platform	O
which	O
runs	O
on	O
many	O
OSs	O
and	O
hardware	O
types	O
.	O
</s>
<s>
A	O
hardware	B-Device
platform	I-Device
can	O
refer	O
to	O
an	O
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
.	O
</s>
<s>
For	O
example	O
:	O
x86	B-Operating_System
architecture	I-Operating_System
and	O
its	O
variants	O
such	O
as	O
IA-32	B-Device
and	O
x86-64	B-Device
.	O
</s>
<s>
These	O
machines	O
often	O
run	O
one	O
version	O
of	O
Microsoft	B-Application
Windows	I-Application
,	O
though	O
they	O
can	O
run	O
other	O
OSs	O
including	O
Linux	B-Application
,	O
OpenBSD	B-Operating_System
,	O
NetBSD	B-Device
,	O
macOS	B-Application
and	O
FreeBSD	B-Operating_System
.	O
</s>
<s>
The	O
32-bit	O
ARM	B-Architecture
architectures	I-Architecture
(	O
and	O
newer	O
64-bit	B-Device
version	O
)	O
is	O
common	O
on	O
smartphones	B-Operating_System
and	O
tablet	B-Device
computers	I-Device
,	O
which	O
run	O
Android	B-Application
,	O
iOS	B-Application
and	O
other	O
mobile	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
.	O
</s>
<s>
A	O
software	B-Device
platform	I-Device
can	O
be	O
either	O
an	O
OS	O
or	O
programming	B-Application
environment	I-Application
,	O
though	O
more	O
commonly	O
it	O
is	O
a	O
combination	O
of	O
both	O
.	O
</s>
<s>
An	O
exception	O
is	O
Java	B-Device
,	O
which	O
uses	O
an	O
OS-independent	O
VM	O
to	O
execute	O
Java	B-Language
bytecode	I-Language
.	O
</s>
<s>
Examples	O
of	O
software	B-Device
platforms	I-Device
are	O
:	O
</s>
<s>
The	O
Java	B-Language
language	I-Language
is	O
typically	O
compiled	B-Language
to	O
run	O
on	O
a	O
VM	O
that	O
is	O
part	O
of	O
the	O
Java	B-Device
platform	I-Device
.	O
</s>
<s>
The	O
Java	B-Language
VM	I-Language
(	O
JVM	B-Language
)	O
is	O
a	O
CPU	O
implemented	O
in	O
software	O
,	O
which	O
runs	O
all	O
Java	B-Language
code	I-Language
.	O
</s>
<s>
This	O
enables	O
the	O
same	O
code	O
to	O
run	O
on	O
all	O
systems	O
that	O
implement	O
a	O
JVM	B-Language
.	O
</s>
<s>
Java	B-Device
software	O
can	O
be	O
executed	O
by	O
a	O
hardware-based	O
Java	B-Language
processor	I-Language
.	O
</s>
<s>
Java	B-Language
code	I-Language
running	O
in	O
the	O
JVM	B-Language
has	O
access	O
to	O
OS-related	O
services	O
,	O
like	O
disk	O
I/O	O
and	O
network	O
access	O
,	O
if	O
the	O
appropriate	O
privileges	O
are	O
granted	O
.	O
</s>
<s>
The	O
JVM	B-Language
makes	O
the	O
system	O
calls	O
on	O
behalf	O
of	O
the	O
Java	B-Device
application	B-Application
.	O
</s>
<s>
For	O
example	O
,	O
disk	O
and	O
network	O
access	O
is	O
usually	O
enabled	O
for	O
desktop	B-Application
applications	I-Application
,	O
but	O
not	O
for	O
browser-based	B-Application
applets	B-Language
.	O
</s>
<s>
The	O
Java	B-Language
Native	I-Language
Interface	I-Language
(	O
JNI	B-Language
)	O
can	O
also	O
be	O
used	O
to	O
access	O
OS-specific	O
functions	O
,	O
with	O
a	O
loss	O
of	O
portability	B-Architecture
.	O
</s>
<s>
Currently	O
,	O
Java	B-Device
Standard	O
Edition	O
software	O
can	O
run	O
on	O
Microsoft	B-Application
Windows	I-Application
,	O
macOS	B-Application
,	O
several	O
Unix-like	B-Operating_System
OSs	O
,	O
and	O
several	O
real-time	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
for	O
embedded	O
devices	O
.	O
</s>
<s>
For	O
mobile	O
applications	O
,	O
browser	B-Application
plugins	O
are	O
used	O
for	O
Windows	B-Application
and	O
Mac	B-Device
based	O
devices	O
,	O
and	O
Android	B-Application
has	O
built-in	O
support	O
for	O
Java	B-Device
.	O
</s>
<s>
There	O
are	O
also	O
subsets	O
of	O
Java	B-Device
,	O
such	O
as	O
Java	B-Language
Card	I-Language
or	O
Java	B-Language
Platform	I-Language
,	I-Language
Micro	I-Language
Edition	I-Language
,	O
designed	O
for	O
resource-constrained	O
devices	O
.	O
</s>
<s>
For	O
software	O
to	O
be	O
considered	O
cross-platform	B-Operating_System
,	O
it	O
must	O
function	O
on	O
more	O
than	O
one	O
computer	B-General_Concept
architecture	I-General_Concept
or	O
OS	O
.	O
</s>
<s>
Developing	O
such	O
software	O
can	O
be	O
a	O
time-consuming	O
task	O
because	O
different	O
OSs	O
have	O
different	O
application	B-Application
programming	I-Application
interfaces	I-Application
(	O
API	B-Application
)	O
.	O
</s>
<s>
For	O
example	O
,	O
Linux	B-Application
uses	O
a	O
different	O
API	B-Application
from	O
Windows	B-Application
.	O
</s>
<s>
One	O
example	O
is	O
OpenOffice.org,	O
which	O
in	O
2006	O
did	O
not	O
natively	O
run	O
on	O
AMD64	B-Device
or	O
Intel	O
64	O
processors	O
implementing	O
the	O
x86-64	B-Device
standards	O
;	O
by	O
2012	O
it	O
was	O
"	O
mostly	O
"	O
ported	O
to	O
these	O
systems	O
.	O
</s>
<s>
Just	O
because	O
software	O
is	O
written	O
in	O
a	O
popular	O
programming	O
language	O
such	O
as	O
C	B-Language
or	O
C++	B-Language
,	O
it	O
does	O
not	O
mean	O
it	O
will	O
run	O
on	O
all	O
OSs	O
that	O
support	O
that	O
language	O
—	O
or	O
even	O
on	O
different	O
versions	O
of	O
the	O
same	O
OS	O
.	O
</s>
<s>
Web	B-Application
applications	I-Application
are	O
typically	O
described	O
as	O
cross-platform	B-Operating_System
because	O
,	O
ideally	O
,	O
they	O
are	O
accessible	O
from	O
any	O
web	B-Application
browser	I-Application
:	O
the	O
browser	B-Application
is	O
the	O
platform	O
.	O
</s>
<s>
Web	B-Application
applications	I-Application
generally	O
employ	O
a	O
client	B-Operating_System
–	I-Operating_System
server	I-Operating_System
model	I-Operating_System
,	O
but	O
vary	O
widely	O
in	O
complexity	O
and	O
functionality	O
.	O
</s>
<s>
Basic	O
web	B-Application
applications	I-Application
perform	O
all	O
or	O
most	O
processing	O
from	O
a	O
stateless	B-Protocol
server	I-Protocol
,	O
and	O
pass	O
the	O
result	O
to	O
the	O
client	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
All	O
user	O
interaction	O
with	O
the	O
application	B-Application
consists	O
of	O
simple	O
exchanges	O
of	O
data	O
requests	O
and	O
server	O
responses	O
.	O
</s>
<s>
This	O
type	O
of	O
application	B-Application
was	O
the	O
norm	O
in	O
the	O
early	O
phases	O
of	O
World	O
Wide	O
Web	B-Application
application	I-Application
development	I-Application
.	O
</s>
<s>
Such	O
applications	O
follow	O
a	O
simple	O
transaction	B-General_Concept
model	O
,	O
identical	O
to	O
that	O
of	O
serving	O
static	O
web	O
pages	O
.	O
</s>
<s>
Today	O
,	O
they	O
are	O
still	O
relatively	O
common	O
,	O
especially	O
where	O
cross-platform	B-Operating_System
compatibility	O
and	O
simplicity	O
are	O
deemed	O
more	O
critical	O
than	O
advanced	O
functionality	O
.	O
</s>
<s>
Prominent	O
examples	O
of	O
advanced	O
web	B-Application
applications	I-Application
include	O
the	O
Web	O
interface	O
to	O
Gmail	B-Application
,	O
A9.com,	O
Google	B-Application
Maps	I-Application
website	O
,	O
and	O
the	O
Live	B-Application
Search	I-Application
service	O
(	O
now	O
Bing	B-Application
)	O
from	O
Microsoft	O
.	O
</s>
<s>
Such	O
applications	O
routinely	O
depend	O
on	O
additional	O
features	O
found	O
only	O
in	O
the	O
more	O
recent	O
versions	O
of	O
popular	O
web	B-Application
browsers	I-Application
.	O
</s>
<s>
These	O
features	O
include	O
Ajax	B-General_Concept
,	O
JavaScript	B-Language
,	O
Dynamic	B-General_Concept
HTML	I-General_Concept
,	O
SVG	B-Application
,	O
and	O
other	O
components	O
of	O
rich	B-Application
web	I-Application
applications	I-Application
.	O
</s>
<s>
Graceful	O
degradation	O
attempts	O
to	O
provide	O
the	O
same	O
or	O
similar	O
functionality	O
to	O
all	O
users	O
and	O
platforms	B-Device
,	O
while	O
diminishing	O
that	O
functionality	O
to	O
a	O
least	O
common	O
denominator	O
for	O
more	O
limited	O
client	O
browsers	B-Application
.	O
</s>
<s>
For	O
example	O
,	O
a	O
user	O
attempting	O
to	O
use	O
a	O
limited-feature	O
browser	B-Application
to	O
access	O
Gmail	B-Application
may	O
notice	O
that	O
Gmail	B-Application
switches	O
to	O
basic	O
mode	O
,	O
with	O
reduced	O
functionality	O
but	O
still	O
of	O
use	O
.	O
</s>
<s>
Some	O
software	O
is	O
maintained	O
in	O
distinct	O
codebases	O
for	O
different	O
(	O
hardware	O
and	O
OS	O
)	O
platforms	B-Device
,	O
with	O
equivalent	O
functionality	O
.	O
</s>
<s>
This	O
strategy	O
relies	O
on	O
having	O
one	O
codebase	O
that	O
may	O
be	O
compiled	B-Language
to	O
multiple	O
platform-specific	O
formats	O
.	O
</s>
<s>
One	O
technique	O
is	O
conditional	B-Application
compilation	I-Application
.	O
</s>
<s>
With	O
this	O
technique	O
,	O
code	O
that	O
is	O
common	O
to	O
all	O
platforms	B-Device
is	O
not	O
repeated	O
.	O
</s>
<s>
Blocks	O
of	O
code	O
that	O
are	O
only	O
relevant	O
to	O
certain	O
platforms	B-Device
are	O
made	O
conditional	O
,	O
so	O
that	O
they	O
are	O
only	O
interpreted	B-Application
or	O
compiled	B-Language
when	O
needed	O
.	O
</s>
<s>
Another	O
technique	O
is	O
separation	O
of	O
functionality	O
,	O
which	O
disables	O
functionality	O
not	O
supported	O
by	O
browsers	B-Application
or	O
OSs	O
,	O
while	O
still	O
delivering	O
a	O
complete	O
application	B-Application
to	O
the	O
user	O
.	O
</s>
<s>
This	O
technique	O
is	O
used	O
in	O
web	O
development	O
where	O
interpreted	B-Application
code	O
(	O
as	O
in	O
scripting	B-Language
languages	I-Language
)	O
can	O
query	O
the	O
platform	O
it	O
is	O
running	O
on	O
to	O
execute	O
different	O
blocks	O
conditionally	O
.	O
</s>
<s>
Third-party	O
libraries	O
attempt	O
to	O
simplify	O
cross-platform	B-Operating_System
capability	O
by	O
hiding	O
the	O
complexities	O
of	O
client	O
differentiation	O
behind	O
a	O
single	O
,	O
unified	O
API	B-Application
,	O
at	O
the	O
expense	O
of	O
vendor	O
lock-in	O
.	O
</s>
<s>
Responsive	B-General_Concept
web	I-General_Concept
design	I-General_Concept
(	O
RWD	O
)	O
is	O
a	O
Web	O
design	O
approach	O
aimed	O
at	O
crafting	O
the	O
visual	O
layout	O
of	O
sites	O
to	O
provide	O
an	O
optimal	O
viewing	O
experience	O
—	O
easy	O
reading	O
and	O
navigation	O
with	O
a	O
minimum	O
of	O
resizing	O
,	O
panning	O
,	O
and	O
scrolling	O
—	O
across	O
a	O
wide	O
range	O
of	O
devices	O
,	O
from	O
mobile	O
phones	O
to	O
desktop	O
computer	O
monitors	O
.	O
</s>
<s>
Cross-platform	B-Operating_System
applications	O
need	O
much	O
more	O
integration	O
testing	O
.	O
</s>
<s>
Some	O
web	B-Application
browsers	I-Application
prohibit	O
installation	O
of	O
different	O
versions	O
on	O
the	O
same	O
machine	O
.	O
</s>
<s>
There	O
are	O
several	O
approaches	O
used	O
to	O
target	O
multiple	B-Operating_System
platforms	I-Operating_System
,	O
but	O
all	O
of	O
them	O
result	O
in	O
software	O
that	O
requires	O
substantial	O
manual	O
effort	O
for	O
testing	O
and	O
maintenance	O
.	O
</s>
<s>
Techniques	O
such	O
as	O
full	B-Architecture
virtualization	I-Architecture
are	O
sometimes	O
used	O
as	O
a	O
workaround	O
for	O
this	O
problem	O
.	O
</s>
<s>
Tools	O
such	O
as	O
the	O
Page	O
Object	O
Model	O
allow	O
cross-platform	B-Operating_System
tests	O
to	O
be	O
scripted	O
so	O
that	O
one	O
test	O
case	O
covers	O
multiple	O
versions	O
of	O
an	O
app	O
.	O
</s>
<s>
Web	B-Application
applications	I-Application
are	O
becoming	O
increasingly	O
popular	O
but	O
many	O
computer	O
users	O
still	O
use	O
traditional	O
application	B-Application
software	I-Application
which	O
does	O
not	O
rely	O
on	O
a	O
client/web	O
-server	O
architecture	O
.	O
</s>
<s>
The	O
distinction	O
between	O
traditional	O
and	O
web	B-Application
applications	I-Application
is	O
not	O
always	O
clear	O
.	O
</s>
<s>
Traditional	O
application	B-Application
software	I-Application
has	O
been	O
distributed	O
as	O
binary	O
files	O
,	O
especially	O
executable	B-Application
files	I-Application
.	O
</s>
<s>
Executables	B-Application
only	O
support	O
platform	O
they	O
were	O
built	O
for	O
—	O
which	O
means	O
that	O
a	O
single	O
cross-platform	B-Operating_System
executable	B-Application
could	O
be	O
very	O
bloated	O
with	O
code	O
that	O
never	O
executes	O
on	O
a	O
particular	O
platform	O
.	O
</s>
<s>
Instead	O
,	O
generally	O
there	O
is	O
a	O
selection	O
of	O
executables	B-Application
,	O
each	O
built	O
for	O
one	O
platform	O
.	O
</s>
<s>
For	O
software	O
that	O
is	O
distributed	O
as	O
a	O
binary	B-Application
executable	I-Application
,	O
such	O
as	O
that	O
written	O
in	O
C	B-Language
or	O
C++	B-Language
,	O
there	O
must	O
be	O
a	O
software	O
build	O
for	O
each	O
platform	O
,	O
using	O
a	O
toolset	O
that	O
translates	O
—	O
transcompiles	B-Language
—	O
a	O
single	O
codebase	O
into	O
multiple	O
binary	B-Application
executables	I-Application
.	O
</s>
<s>
For	O
example	O
,	O
Firefox	B-Application
,	O
an	O
open-source	B-Application
web	B-Application
browser	I-Application
,	O
is	O
available	O
on	O
Windows	B-Application
,	O
macOS	B-Application
(	O
both	O
PowerPC	B-Architecture
and	O
x86	B-Operating_System
through	O
what	O
Apple	O
Inc	O
.	O
calls	O
a	O
Universal	B-Operating_System
binary	I-Operating_System
)	O
,	O
Linux	B-Application
,	O
and	O
BSD	B-Operating_System
on	O
multiple	O
computer	B-General_Concept
architectures	I-General_Concept
.	O
</s>
<s>
The	O
four	O
platforms	B-Device
(	O
in	O
this	O
case	O
,	O
Windows	B-Application
,	O
macOS	B-Application
,	O
Linux	B-Application
,	O
and	O
BSD	B-Operating_System
)	O
are	O
separate	O
executable	B-Application
distributions	O
,	O
although	O
they	O
come	O
largely	O
from	O
the	O
same	O
source	O
code	O
.	O
</s>
<s>
In	O
rare	O
cases	O
,	O
executable	B-Application
code	I-Application
built	O
for	O
several	O
platforms	B-Device
is	O
combined	O
into	O
a	O
single	O
executable	B-Application
file	I-Application
called	O
a	O
fat	O
binary	O
.	O
</s>
<s>
The	O
use	O
of	O
different	O
toolsets	O
may	O
not	O
be	O
enough	O
to	O
build	O
a	O
working	O
executables	B-Application
for	O
different	O
platforms	B-Device
.	O
</s>
<s>
For	O
example	O
,	O
an	O
application	B-Application
such	O
as	O
Firefox	B-Application
,	O
which	O
already	O
runs	O
on	O
Windows	B-Application
on	O
the	O
x86	B-Operating_System
family	O
,	O
can	O
be	O
modified	O
and	O
re-built	O
to	O
run	O
on	O
Linux	B-Application
on	O
the	O
x86	B-Operating_System
(	O
and	O
potentially	O
other	O
architectures	O
)	O
as	O
well	O
.	O
</s>
<s>
An	O
alternative	O
to	O
porting	O
is	O
cross-platform	B-General_Concept
virtualization	I-General_Concept
,	O
where	O
applications	O
compiled	B-Language
for	O
one	O
platform	O
can	O
run	O
on	O
another	O
without	O
modification	O
of	O
the	O
source	O
code	O
or	O
binaries	O
.	O
</s>
<s>
As	O
an	O
example	O
,	O
Apple	O
's	O
Rosetta	B-Operating_System
,	O
which	O
is	O
built	O
into	O
Intel-based	O
Macintosh	B-Device
computers	I-Device
,	O
runs	O
applications	O
compiled	B-Language
for	O
the	O
previous	O
generation	O
of	O
Macs	B-Device
that	O
used	O
PowerPC	B-Architecture
CPUs	O
.	O
</s>
<s>
Another	O
example	O
is	O
IBM	O
PowerVM	B-Device
Lx86	I-Device
,	O
which	O
allows	O
Linux/x86	O
applications	O
to	O
run	O
unmodified	O
on	O
the	O
Linux/Power	O
OS	O
.	O
</s>
<s>
Example	O
of	O
cross-platform	B-Operating_System
binary	O
software	O
:	O
</s>
<s>
The	O
LibreOffice	B-Application
office	O
suite	O
is	O
built	O
for	O
Microsoft	B-Application
Windows	I-Application
,	O
macOS	B-Application
,	O
many	O
Linux	B-Application
distributions	O
,	O
FreeBSD	B-Operating_System
,	O
NetBSD	B-Device
,	O
OpenBSD	B-Operating_System
,	O
Android	B-Application
,	O
iOS	B-Application
,	O
iPadOS	B-Operating_System
,	O
ChromeOS	B-Operating_System
,	O
web-based	B-Application
Collabora	B-General_Concept
Online	I-General_Concept
and	O
many	O
others	O
.	O
</s>
<s>
A	O
script	O
can	O
be	O
considered	O
to	O
be	O
cross-platform	B-Operating_System
if	O
its	O
interpreter	B-Application
is	O
available	O
on	O
multiple	B-Operating_System
platforms	I-Operating_System
and	O
the	O
script	O
only	O
uses	O
the	O
facilities	O
built	O
into	O
the	O
language	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
script	O
written	O
in	O
Python	B-Language
for	O
a	O
Unix-like	B-Operating_System
system	I-Operating_System
will	O
likely	O
run	O
with	O
little	O
or	O
no	O
modification	O
on	O
Windows	B-Application
,	O
because	O
Python	B-Language
also	O
runs	O
on	O
Windows	B-Application
;	O
indeed	O
there	O
are	O
many	O
implementations	O
(	O
e.g.	O
</s>
<s>
IronPython	B-Application
for	O
.NET	B-Application
Framework	I-Application
)	O
.	O
</s>
<s>
The	O
same	O
goes	O
for	O
many	O
of	O
the	O
open-source	B-Application
scripting	B-Language
languages	I-Language
.	O
</s>
<s>
Unlike	O
binary	B-Application
executable	I-Application
files	O
,	O
the	O
same	O
script	O
can	O
be	O
used	O
on	O
all	O
computers	O
that	O
have	O
software	O
to	O
interpret	O
the	O
script	O
.	O
</s>
<s>
This	O
is	O
because	O
the	O
script	O
is	O
generally	O
stored	O
in	O
plain	O
text	O
in	O
a	O
text	B-General_Concept
file	I-General_Concept
.	O
</s>
<s>
Some	O
popular	O
cross-platform	B-Operating_System
scripting	B-Language
languages	I-Language
are	O
:	O
</s>
<s>
bash	B-Operating_System
–	O
A	O
Unix	B-Application
shell	I-Application
commonly	O
run	O
on	O
Linux	B-Application
and	O
other	O
modern	O
Unix-like	B-Operating_System
systems	I-Operating_System
,	O
as	O
well	O
as	O
on	O
Windows	B-Application
via	O
the	O
Cygwin	B-Language
POSIX	O
compatibility	O
layer	O
.	O
</s>
<s>
Perl	B-Language
–	O
First	O
released	O
in	O
1987	O
.	O
</s>
<s>
Used	O
for	O
CGI	B-Language
programming	O
,	O
small	O
system	B-Application
administration	I-Application
tasks	O
,	O
and	O
more	O
.	O
</s>
<s>
PHP	B-Application
–	O
Mostly	O
used	O
for	O
web	B-Application
applications	I-Application
.	O
</s>
<s>
Python	B-Language
–	O
A	O
language	O
which	O
focuses	O
on	O
rapid	O
application	B-Application
development	O
and	O
ease	O
of	O
writing	O
,	O
instead	O
of	O
run-time	O
efficiency	O
.	O
</s>
<s>
Ruby	B-Language
–	O
An	O
object-oriented	O
language	O
which	O
aims	O
to	O
be	O
easy	O
to	O
read	O
.	O
</s>
<s>
Can	O
also	O
be	O
used	O
on	O
the	O
web	O
through	O
Ruby	B-Application
on	I-Application
Rails	I-Application
.	O
</s>
<s>
Tcl	B-Operating_System
–	O
A	O
dynamic	O
programming	O
language	O
,	O
suitable	O
for	O
a	O
wide	O
range	O
of	O
uses	O
,	O
including	O
web	O
and	O
desktop	B-Application
applications	I-Application
,	O
networking	O
,	O
administration	O
,	O
testing	O
and	O
many	O
more	O
.	O
</s>
<s>
Cross-platform	B-Operating_System
or	O
multi-platform	B-Operating_System
is	O
a	O
term	O
that	O
can	O
also	O
apply	O
to	O
video	O
games	O
released	O
on	O
a	O
range	O
of	O
video	B-Device
game	I-Device
consoles	I-Device
.	O
</s>
<s>
Examples	O
of	O
cross-platform	B-Operating_System
games	O
include	O
:	O
Miner	B-Application
2049er	I-Application
,	O
Tomb	B-Application
Raider	I-Application
:	I-Application
Legend	I-Application
,	O
FIFA	O
series	O
,	O
NHL	O
series	O
and	O
Minecraft	B-Application
.	O
</s>
<s>
Each	O
has	O
been	O
released	O
across	O
a	O
variety	O
of	O
gaming	O
platforms	B-Device
,	O
such	O
as	O
the	B-Operating_System
Wii	I-Operating_System
,	O
PlayStation	B-Operating_System
3	I-Operating_System
,	O
Xbox	B-Operating_System
360	I-Operating_System
,	O
personal	B-Device
computers	I-Device
,	O
and	O
mobile	B-Application
devices	I-Application
.	O
</s>
<s>
Some	O
platforms	B-Device
are	O
harder	O
to	O
write	O
for	O
than	O
others	O
.	O
</s>
<s>
To	O
offset	O
this	O
,	O
a	O
video	O
game	O
may	O
be	O
released	O
on	O
a	O
few	O
platforms	B-Device
first	O
,	O
then	O
later	O
on	O
others	O
.	O
</s>
<s>
Typically	O
,	O
this	O
happens	O
when	O
a	O
new	O
gaming	O
system	O
is	O
released	O
,	O
because	O
video	O
game	O
developers	O
need	O
to	O
acquaint	O
themselves	O
with	O
its	O
hardware	O
and	O
software	B-Application
.	I-Application
</s>
<s>
Some	O
games	O
may	O
not	O
be	O
cross-platform	B-Operating_System
because	O
of	O
licensing	O
agreements	O
between	O
developers	O
and	O
video	B-Device
game	I-Device
console	I-Device
manufacturers	O
that	O
limit	O
development	O
to	O
one	O
particular	O
console	O
.	O
</s>
<s>
Several	O
developers	O
have	O
implemented	O
ways	O
to	O
play	O
games	B-Application
online	I-Application
while	O
using	O
different	O
platforms	B-Device
.	O
</s>
<s>
Psyonix	O
,	O
Epic	O
Games	O
,	O
Microsoft	O
,	O
and	O
Valve	O
all	O
possess	O
technology	O
that	O
allows	O
Xbox	B-Operating_System
360	I-Operating_System
and	O
PlayStation	B-Operating_System
3	I-Operating_System
gamers	O
to	O
play	O
with	O
PC	O
gamers	O
,	O
leaving	O
the	O
decision	O
of	O
which	O
platform	O
to	O
use	O
to	O
consumers	O
.	O
</s>
<s>
The	O
first	O
game	O
to	O
allow	O
this	O
level	O
of	O
interactivity	O
between	O
PC	O
and	O
console	O
games	O
was	O
Quake	B-Application
3	I-Application
.	O
</s>
<s>
Games	O
that	O
feature	O
cross-platform	B-Operating_System
online	B-Application
play	I-Application
include	O
Rocket	B-Application
League	I-Application
,	O
Final	B-Protocol
Fantasy	I-Protocol
XIV	I-Protocol
,	O
Street	B-Application
Fighter	I-Application
V	I-Application
,	O
Killer	B-Application
Instinct	I-Application
,	O
Paragon	B-Application
and	O
Fable	B-Application
Fortune	I-Application
,	O
and	O
Minecraft	B-Application
with	O
its	O
Better	O
Together	O
update	O
on	O
Windows	B-Operating_System
10	I-Operating_System
,	O
VR	O
editions	O
,	O
Pocket	O
Edition	O
and	O
Xbox	B-Device
One	I-Device
.	O
</s>
<s>
Cross-platform	B-Operating_System
programming	O
is	O
the	O
practice	O
of	O
deliberately	O
writing	O
software	O
to	O
work	O
on	O
more	O
than	O
one	O
platform	O
.	O
</s>
<s>
There	O
are	O
different	O
ways	O
to	O
write	O
a	O
cross-platform	B-Operating_System
application	B-Application
.	O
</s>
<s>
One	O
approach	O
is	O
to	O
create	O
multiple	O
versions	O
of	O
the	O
same	O
software	O
in	O
different	O
source	O
trees	O
—	O
in	O
other	O
words	O
,	O
the	O
Microsoft	B-Application
Windows	I-Application
version	O
of	O
an	O
application	B-Application
might	O
have	O
one	O
set	O
of	O
source	O
code	O
files	O
and	O
the	O
Macintosh	B-Device
version	O
another	O
,	O
while	O
a	O
FOSS	B-License
*	B-Operating_System
nix	I-Operating_System
system	O
might	O
have	O
a	O
third	O
.	O
</s>
<s>
Another	O
approach	O
is	O
to	O
use	O
software	O
that	O
hides	O
the	O
differences	O
between	O
the	O
platforms	B-Device
.	O
</s>
<s>
This	O
abstraction	B-Architecture
layer	I-Architecture
insulates	O
the	O
application	B-Application
from	O
the	O
platform	O
.	O
</s>
<s>
Such	O
applications	O
are	O
platform	B-Operating_System
agnostic	I-Operating_System
.	O
</s>
<s>
Applications	O
that	O
run	O
on	O
the	O
JVM	B-Language
are	O
built	O
this	O
way	O
.	O
</s>
<s>
Some	O
applications	O
mix	O
various	O
methods	O
of	O
cross-platform	B-Operating_System
programming	O
to	O
create	O
the	O
final	O
application	B-Application
.	O
</s>
<s>
An	O
example	O
is	O
the	O
Firefox	B-Application
web	I-Application
browser	I-Application
,	O
which	O
uses	O
abstraction	O
to	O
build	O
some	O
of	O
the	O
lower-level	O
components	O
,	O
with	O
separate	O
source	O
subtrees	O
for	O
implementing	O
platform-specific	O
features	O
(	O
like	O
the	O
GUI	O
)	O
,	O
and	O
the	O
implementation	O
of	O
more	O
than	O
one	O
scripting	B-Language
language	I-Language
to	O
ease	O
software	B-Architecture
portability	I-Architecture
.	O
</s>
<s>
Firefox	B-Application
implements	O
XUL	B-Application
,	O
CSS	B-Language
and	O
JavaScript	B-Language
for	O
extending	O
the	O
browser	B-Application
,	O
in	O
addition	O
to	O
classic	O
Netscape-style	O
browser	B-Application
plugins	O
.	O
</s>
<s>
Much	O
of	O
the	O
browser	B-Application
itself	O
is	O
written	O
in	O
XUL	B-Application
,	O
CSS	B-Language
,	O
and	O
JavaScript	B-Language
.	O
</s>
<s>
There	O
are	O
many	O
tools	O
available	O
to	O
help	O
the	O
process	O
of	O
cross-platform	B-Operating_System
programming	O
:	O
</s>
<s>
8th	O
:	O
a	O
development	O
language	O
which	O
utilizes	O
Juce	B-Language
as	O
its	O
GUI	O
layer	O
.	O
</s>
<s>
It	O
currently	O
supports	O
Android	B-Application
,	O
iOS	B-Application
,	O
Windows	B-Application
,	O
macOS	B-Application
,	O
Linux	B-Application
and	O
Raspberry	B-Operating_System
Pi	I-Operating_System
.	O
</s>
<s>
Anant	O
Computing	O
:	O
A	O
mobile	O
application	B-Device
platform	I-Device
that	O
works	O
in	O
all	O
Indian	O
languages	O
,	O
including	O
their	O
keyboards	O
,	O
and	O
also	O
supports	O
AppWallet	O
and	O
native	O
performance	O
in	O
all	O
OSs	O
.	O
</s>
<s>
Natively	O
developed	O
containers	O
present	O
hardware	O
features	O
of	O
the	O
mobile	B-Application
devices	I-Application
or	O
tablets	B-Device
through	O
an	O
API	B-Application
to	O
HTML5	O
code	O
thus	O
facilitating	O
the	O
development	O
of	O
mobile	O
apps	O
that	O
run	O
on	O
different	O
platforms	B-Device
.	O
</s>
<s>
Boden	O
:	O
a	O
UI	O
framework	O
written	O
in	O
C++	B-Language
.	O
</s>
<s>
Cairo	B-Language
:	O
a	O
free	B-Application
software	I-Application
library	O
used	O
to	O
provide	O
a	O
vector	O
graphics-based	O
,	O
device-independent	O
API	B-Application
.	O
</s>
<s>
Cairo	B-Language
is	O
written	O
in	O
C	B-Language
and	O
has	O
bindings	O
for	O
many	O
programming	O
languages	O
.	O
</s>
<s>
Cocos2d	B-Application
:	O
an	O
open-source	B-Application
toolkit	O
and	O
game	O
engine	O
for	O
developing	O
2D	O
and	O
simple	O
3D	O
cross-platform	B-Operating_System
games	O
and	O
applications	O
.	O
</s>
<s>
Codename	B-Language
One	I-Language
:	O
an	O
open-source	B-Application
Write	O
Once	O
Run	O
Anywhere	O
(	O
WORA	O
)	O
framework	O
for	O
Java	B-Device
and	O
Kotlin	O
developers	O
.	O
</s>
<s>
Delphi	B-Language
:	O
an	O
IDE	O
which	O
uses	O
a	O
Pascal-based	O
language	O
for	O
development	O
.	O
</s>
<s>
It	O
supports	O
Android	B-Application
,	O
iOS	B-Application
,	O
Windows	B-Application
,	O
macOS	B-Application
,	O
Linux	B-Application
.	O
</s>
<s>
Ecere	O
SDK	O
:	O
a	O
GUI	O
and	O
2D/3D	O
graphics	O
toolkit	O
and	O
IDE	O
,	O
written	O
in	O
eC	B-Language
and	O
with	O
support	O
for	O
additional	O
languages	O
such	O
as	O
C	B-Language
and	O
Python	B-Language
.	O
</s>
<s>
It	O
supports	O
Linux	B-Application
,	O
FreeBSD	B-Operating_System
,	O
Windows	B-Application
,	O
Android	B-Application
,	O
macOS	B-Application
and	O
the	O
Web	O
through	O
Emscripten	O
or	O
Binaryen	O
(	O
WebAssembly	O
)	O
.	O
</s>
<s>
Eclipse	B-Application
:	O
an	O
open-source	B-Application
development	O
environment	O
.	O
</s>
<s>
Implemented	O
in	O
Java	B-Device
with	O
a	O
configurable	O
architecture	O
which	O
supports	O
many	O
tools	O
for	O
software	O
development	O
.	O
</s>
<s>
Add-ons	O
are	O
available	O
for	O
several	O
languages	O
,	O
including	O
Java	B-Device
and	O
C++	B-Language
.	O
</s>
<s>
FLTK	B-Language
:	O
an	O
open-source	B-Application
toolkit	O
,	O
but	O
more	O
lightweight	O
because	O
it	O
restricts	O
itself	O
to	O
the	O
GUI	O
.	O
</s>
<s>
Flutter	B-Application
:	O
A	O
cross-platform	B-Operating_System
UI	O
framework	O
for	O
Android	B-Application
and	O
iOS	B-Application
developed	O
by	O
Google	B-Application
.	I-Application
</s>
<s>
fpGUI	B-Language
:	O
An	O
open-source	B-Application
widget	B-Library
toolkit	I-Library
that	O
is	O
completely	O
implemented	O
in	O
Object	O
Pascal	O
.	O
</s>
<s>
It	O
currently	O
supports	O
Linux	B-Application
,	O
Windows	B-Application
and	O
a	O
bit	O
of	O
Windows	B-Application
CE	O
.	O
</s>
<s>
GeneXus	B-Application
:	O
A	O
Windows	B-Application
rapid	O
software	O
development	O
solution	O
for	O
cross-platform	B-Operating_System
application	B-Application
creation	O
and	O
deployment	O
based	O
on	O
knowledge	O
representation	O
and	O
supporting	O
C#	B-Application
,	O
COBOL	B-Application
,	O
Java	B-Device
including	O
Android	B-Application
and	O
BlackBerry	O
smart	O
devices	O
,	O
Objective-C	B-Language
for	O
Apple	O
mobile	B-Application
devices	I-Application
,	O
RPG	B-Language
,	O
Ruby	B-Language
,	O
Visual	B-Language
Basic	I-Language
,	O
and	O
Visual	B-Application
FoxPro	I-Application
.	O
</s>
<s>
GLBasic	B-Language
:	O
A	O
BASIC	O
dialect	O
and	O
compiler	B-Language
that	O
generates	O
C++	B-Language
code	O
.	O
</s>
<s>
It	O
includes	O
cross	O
compilers	B-Language
for	O
many	O
platforms	B-Device
and	O
supports	O
numerous	O
platform	O
(	O
Windows	B-Application
,	O
Mac	B-Device
,	O
Linux	B-Application
,	O
Android	B-Application
,	O
iOS	B-Application
and	O
some	O
exotic	O
handhelds	B-Application
)	O
.	O
</s>
<s>
Godot	B-Application
:	O
an	O
SDK	O
which	O
uses	O
Godot	B-Application
Engine	I-Application
.	O
</s>
<s>
GTK+	B-Application
:	O
An	O
open-source	B-Application
widget	B-Library
toolkit	I-Library
for	O
Unix-like	B-Operating_System
systems	I-Operating_System
with	O
X11	B-Operating_System
and	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
<s>
Haxe	B-Language
:	O
An	O
open-source	B-Application
language	O
.	O
</s>
<s>
Juce	B-Language
:	O
An	O
application	B-Application
framework	I-Application
written	O
in	O
C++	B-Language
,	O
used	O
to	O
write	O
native	O
software	O
on	O
numerous	O
systems	O
(	O
Microsoft	B-Application
Windows	I-Application
,	O
POSIX	O
,	O
macOS	B-Application
)	O
,	O
with	O
no	O
change	O
to	O
the	O
code	O
.	O
</s>
<s>
Kivy	B-Language
:	O
an	O
open-source	B-Application
cross-platform	B-Operating_System
UI	O
framework	O
written	O
in	O
Python	B-Language
.	O
</s>
<s>
It	O
supports	O
Android	B-Application
,	O
iOS	B-Application
,	O
Linux	B-Application
,	O
OS	B-Application
X	I-Application
,	O
Windows	B-Application
and	O
Raspberry	B-Operating_System
Pi	I-Operating_System
.	O
</s>
<s>
LEADTOOLS	O
:	O
Cross-platform	B-Operating_System
SDK	O
libraries	O
to	O
integrate	O
recognition	O
,	O
document	O
,	O
medical	O
,	O
imaging	O
,	O
and	O
multimedia	O
technologies	O
into	O
Windows	B-Application
,	O
iOS	B-Application
,	O
macOS	B-Application
,	O
Android	B-Application
,	O
Linux	B-Application
and	O
web	B-Application
applications	I-Application
.	O
</s>
<s>
LiveCode	B-Application
:	O
a	O
commercial	O
cross-platform	B-Operating_System
rapid	O
application	B-Application
development	O
language	O
inspired	O
by	O
HyperTalk	O
.	O
</s>
<s>
Lazarus	B-Language
:	O
A	O
programming	B-Application
environment	I-Application
for	O
the	O
FreePascal	O
Compiler	B-Language
.	O
</s>
<s>
It	O
supports	O
the	O
creation	O
of	O
self-standing	O
graphical	O
and	O
console	O
applications	O
and	O
runs	O
on	O
Linux	B-Application
,	O
MacOSX	O
,	O
iOS	B-Application
,	O
Android	B-Application
,	O
WinCE	O
,	O
Windows	B-Application
and	O
WEB	O
.	O
</s>
<s>
Max/MSP	B-Application
:	O
A	O
visual	B-Language
programming	I-Language
language	I-Language
that	O
encapsulates	O
platform-independent	B-Operating_System
code	O
with	O
a	O
platform-specific	O
runtime	O
environment	O
into	O
applications	O
for	O
macOS	B-Application
and	O
Windows	B-Application
A	O
cross-platform	B-Operating_System
Android	B-Application
runtime	O
.	O
</s>
<s>
Mendix	O
:	O
a	O
cloud-based	O
low-code	O
application	B-Application
development	O
platform	O
.	O
</s>
<s>
MonoCross	B-Language
:	O
an	O
open-source	B-Application
model	O
–	O
view	O
–	O
controller	O
design	O
pattern	O
where	O
the	O
model	O
and	O
controller	O
are	O
cross-platform	B-Operating_System
but	O
the	O
view	O
is	O
platform-specific	O
.	O
</s>
<s>
MoSync	B-Application
:	O
an	O
open-source	B-Application
SDK	O
for	O
mobile	B-Application
platform	I-Application
app	O
development	O
in	O
the	O
C++	B-Language
family	O
.	O
</s>
<s>
Mozilla	B-Application
application	I-Application
framework	I-Application
:	O
an	O
open-source	B-Application
platform	I-Application
for	O
building	O
macOS	B-Application
,	O
Windows	B-Application
and	O
Linux	B-Application
applications	O
.	O
</s>
<s>
A	O
cross-platform	B-Operating_System
JavaScript/TypeScript	O
framework	O
for	O
Android	B-Application
and	O
iOS	B-Application
development	O
.	O
</s>
<s>
OpenGL	B-Application
:	O
a	O
3D	O
graphics	O
library	O
.	O
</s>
<s>
Pixel	B-Application
Game	I-Application
Maker	I-Application
MV	I-Application
:	O
A	O
proprietary	O
2D	O
game	O
development	O
software	O
for	O
Windows	B-Application
for	O
developing	O
Windows	B-Application
and	O
Nintendo	B-Application
Switch	I-Application
games	O
.	O
</s>
<s>
PureBasic	B-Application
:	O
a	O
proprietary	O
language	O
and	O
IDE	O
for	O
building	O
macOS	B-Application
,	O
Windows	B-Application
and	O
Linux	B-Application
applications	O
.	O
</s>
<s>
:	O
The	O
universal	O
development	O
SDK	O
to	O
build	O
multi-platform	B-Operating_System
projects	O
with	O
React	B-Application
Native	I-Application
.	O
</s>
<s>
Includes	O
latest	O
iOS	B-Application
,	O
tvOS	O
,	O
Android	B-Application
,	O
Android	B-Application
TV	O
,	O
Web	O
,	O
Tizen	O
TV	O
,	O
Tizen	O
Watch	O
,	O
LG	O
webOS	O
,	O
macOS/OSX	O
,	O
Windows	B-Application
,	O
KaiOS	O
,	O
Firefox	B-Application
OS	O
and	O
Firefox	B-Application
TV	O
platforms	B-Device
.	O
</s>
<s>
Qt	B-Language
:	O
an	O
application	B-Application
framework	I-Application
and	O
widget	B-Library
toolkit	I-Library
for	O
Unix-like	B-Operating_System
systems	I-Operating_System
with	O
X11	B-Operating_System
,	O
Microsoft	B-Application
Windows	I-Application
,	O
macOS	B-Application
,	O
and	O
other	O
systems	O
—	O
available	O
under	O
both	O
proprietary	O
and	O
open-source	B-Application
licenses	O
.	O
</s>
<s>
Simple	B-Language
and	I-Language
Fast	I-Language
Multimedia	I-Language
Library	I-Language
:	O
A	O
multimedia	O
C++	B-Language
API	B-Application
that	O
provides	O
low	O
and	O
high	O
level	O
access	O
to	O
graphics	O
,	O
input	O
,	O
audio	O
,	O
etc	O
.	O
</s>
<s>
Simple	B-Operating_System
DirectMedia	I-Operating_System
Layer	I-Operating_System
:	O
an	O
open-source	B-Application
multimedia	O
library	O
written	O
in	O
C	B-Language
that	O
creates	O
an	O
abstraction	O
over	O
various	O
platforms’	O
graphics	O
,	O
sound	O
,	O
and	O
input	O
APIs	B-Application
.	O
</s>
<s>
It	O
runs	O
on	O
OSs	O
including	O
Linux	B-Application
,	O
Windows	B-Application
and	O
macOS	B-Application
and	O
is	O
aimed	O
at	O
games	O
and	O
multimedia	O
applications	O
.	O
</s>
<s>
Smartface	B-Application
:	O
a	O
native	O
app	O
development	O
tool	O
to	O
create	O
mobile	O
applications	O
for	O
Android	B-Application
and	O
iOS	B-Application
,	O
using	O
WYSIWYG	B-Application
design	O
editor	O
with	O
JavaScript	B-Language
code	O
editor	O
.	O
</s>
<s>
Titanium	B-Application
Mobile	I-Application
:	O
open	O
source	O
cross-platform	B-Operating_System
framework	O
for	O
Android	B-Application
and	O
iOS	B-Application
development	O
.	O
</s>
<s>
Ultimate++	B-Language
:	O
a	O
C++	B-Language
rapid	O
application	B-Application
development	I-Application
framework	I-Application
focused	O
on	O
programmers	O
productivity	O
.	O
</s>
<s>
It	O
includes	O
a	O
set	O
of	O
libraries	O
(	O
GUI	O
,	O
SQL	O
,	O
etc	O
..	O
)	O
,	O
and	O
an	O
integrated	B-Application
development	I-Application
environment	I-Application
.	O
</s>
<s>
It	O
supports	O
Windows	B-Application
and	O
Unix-like	O
OS-s	O
.	O
</s>
<s>
Unity	B-Application
:	O
Another	O
cross-platform	B-Operating_System
SDK	O
which	O
uses	O
Unity	B-Application
Engine	I-Application
.	O
</s>
<s>
Uno	B-Application
Platform	I-Application
:	O
Windows	B-Application
,	O
macOS	B-Application
,	O
iOS	B-Application
,	O
Android	B-Application
,	O
WebAssembly	O
and	O
Linux	B-Application
using	O
C#	B-Application
.	O
</s>
<s>
Unreal	B-Operating_System
:	O
A	O
cross-platform	B-Operating_System
SDK	O
which	O
uses	O
Unreal	B-Operating_System
Engine	I-Operating_System
.	O
</s>
<s>
V-Play	B-Operating_System
Engine	I-Operating_System
:	O
V-Play	O
is	O
a	O
cross-platform	B-Operating_System
development	O
SDK	O
based	O
on	O
the	O
popular	O
Qt	B-Language
framework	I-Language
.	O
</s>
<s>
V-Play	O
apps	O
and	O
games	O
are	O
created	O
within	O
Qt	B-Language
Creator	O
.	O
</s>
<s>
WaveMaker	B-General_Concept
:	O
A	O
low-code	O
development	O
tool	O
to	O
create	O
responsive	O
web	O
and	O
hybrid	O
mobile	O
(	O
Android	B-Application
&	O
iOS	B-Application
)	O
applications	O
.	O
</s>
<s>
WinDev	O
:	O
an	O
Integrated	B-Application
Development	I-Application
Environment	I-Application
for	O
Windows	B-Application
,	O
Linux	B-Application
,	O
.Net	B-Application
and	O
Java	B-Device
,	O
and	O
web	O
browers	O
.	O
</s>
<s>
wxWidgets	B-Language
:	O
an	O
open-source	B-Application
widget	B-Library
toolkit	I-Library
that	O
is	O
also	O
an	O
application	B-Application
framework	I-Application
.	O
</s>
<s>
It	O
runs	O
on	O
Unix-like	B-Operating_System
systems	I-Operating_System
with	O
X11	B-Operating_System
,	O
Microsoft	B-Application
Windows	I-Application
and	O
macOS	B-Application
.	O
</s>
<s>
Xojo	B-Application
:	O
a	O
RAD	O
IDE	O
that	O
uses	O
an	O
object-oriented	O
programming	O
language	O
to	O
create	O
desktop	O
,	O
web	O
and	O
iOS	B-Application
apps	O
.	O
</s>
<s>
Xojo	B-Application
makes	O
native	O
,	O
compiled	B-Language
desktop	B-Application
apps	I-Application
for	O
macOS	B-Application
,	O
Windows	B-Application
,	O
Linux	B-Application
and	O
Raspberry	B-Operating_System
Pi	I-Operating_System
.	O
</s>
<s>
It	O
creates	O
compiled	B-Language
web	B-Application
apps	I-Application
that	O
can	O
be	O
run	O
as	O
standalone	O
servers	O
or	O
through	O
CGI	B-Language
.	O
</s>
<s>
And	O
it	O
recently	O
added	O
the	O
ability	O
to	O
create	O
native	O
iOS	B-Application
apps	O
.	O
</s>
<s>
There	O
are	O
many	O
challenges	O
when	O
developing	O
cross-platform	B-Operating_System
software	I-Operating_System
.	O
</s>
<s>
Testing	O
cross-platform	B-Operating_System
applications	O
may	O
be	O
considerably	O
more	O
complicated	O
,	O
since	O
different	O
platforms	B-Device
can	O
exhibit	O
slightly	O
different	O
behaviors	O
or	O
subtle	O
bugs	O
.	O
</s>
<s>
This	O
problem	O
has	O
led	O
some	O
developers	O
to	O
deride	O
cross-platform	B-Operating_System
development	O
as	O
"	O
write	O
once	O
,	O
debug	O
everywhere	O
"	O
,	O
a	O
take	O
on	O
Sun	O
Microsystems	O
 '	O
"	O
write	O
once	O
,	O
run	O
anywhere	O
"	O
marketing	O
slogan	O
.	O
</s>
<s>
Developers	O
are	O
often	O
restricted	O
to	O
using	O
the	O
lowest	O
common	O
denominator	O
subset	O
of	O
features	O
which	O
are	O
available	O
on	O
all	O
platforms	B-Device
.	O
</s>
<s>
This	O
may	O
hinder	O
the	O
application	B-Application
's	O
performance	O
or	O
prohibit	O
developers	O
from	O
using	O
the	O
most	O
advanced	O
features	O
of	O
each	O
platform	O
.	O
</s>
<s>
Different	O
platforms	B-Device
often	O
have	O
different	O
user	O
interface	O
conventions	O
,	O
which	O
cross-platform	B-Operating_System
applications	O
do	O
not	O
always	O
accommodate	O
.	O
</s>
<s>
For	O
example	O
,	O
applications	O
developed	O
for	O
macOS	B-Application
and	O
GNOME	B-Application
are	O
supposed	O
to	O
place	O
the	O
most	O
important	O
button	O
on	O
the	O
right-hand	O
side	O
of	O
a	O
window	O
or	O
dialog	O
,	O
whereas	O
Microsoft	B-Application
Windows	I-Application
and	O
KDE	B-Application
have	O
the	O
opposite	O
convention	O
.	O
</s>
<s>
Though	O
many	O
of	O
these	O
differences	O
are	O
subtle	O
,	O
a	O
cross-platform	B-Operating_System
application	B-Application
which	O
does	O
not	O
conform	O
to	O
these	O
conventions	O
may	O
feel	O
clunky	O
or	O
alien	O
to	O
the	O
user	O
.	O
</s>
<s>
When	O
working	O
quickly	O
,	O
such	O
opposing	O
conventions	O
may	O
even	O
result	O
in	O
data	B-General_Concept
loss	I-General_Concept
,	O
such	O
as	O
in	O
a	O
dialog	O
box	O
confirming	O
whether	O
to	O
save	O
or	O
discard	O
changes	O
.	O
</s>
<s>
Scripting	B-Language
languages	I-Language
and	O
VM	O
bytecode	O
must	O
be	O
translated	O
into	O
native	O
executable	B-Application
code	I-Application
each	O
time	O
they	O
are	O
used	O
,	O
imposing	O
a	O
performance	O
penalty	O
.	O
</s>
<s>
This	O
penalty	O
can	O
be	O
alleviated	O
using	O
techniques	O
like	O
just-in-time	O
compilation	B-Language
;	O
but	O
some	O
computational	O
overhead	O
may	O
be	O
unavoidable	O
.	O
</s>
<s>
Different	O
platforms	B-Device
require	O
the	O
use	O
of	O
native	O
package	O
formats	O
such	O
as	O
RPM	B-Application
and	O
MSI	B-Application
.	O
</s>
<s>
Multi-platform	B-Operating_System
installers	O
such	O
as	O
InstallAnywhere	B-Application
address	O
this	O
need	O
.	O
</s>
<s>
Cross-platform	B-Operating_System
execution	O
environments	O
may	O
suffer	O
cross-platform	B-Operating_System
security	O
flaws	O
,	O
creating	O
a	O
fertile	O
environment	O
for	O
cross-platform	B-Operating_System
malware	O
.	O
</s>
