<s>
Windows	B-Application
Phone	I-Application
Store	I-Application
(	O
originally	O
known	O
as	O
Windows	B-Application
Phone	I-Application
Marketplace	I-Application
)	O
was	O
an	O
app	B-Application
store	I-Application
platform	O
,	O
developed	O
by	O
Microsoft	O
corporation	O
for	O
Windows	B-Protocol
Phone	I-Protocol
letting	O
users	O
installing	O
various	O
apps	O
on	O
their	O
device	O
.	O
</s>
<s>
It	O
initially	O
launched	O
with	O
Windows	B-Protocol
Phone	I-Protocol
7	O
in	O
October	O
2010	O
.	O
</s>
<s>
With	O
the	O
rollout	O
of	O
Windows	B-Protocol
Phone	I-Protocol
7.5	O
,	O
Microsoft	O
unveiled	O
the	O
online	O
Marketplace	O
that	O
offers	O
,	O
over	O
the	O
air	O
installation	O
of	O
apps	O
.	O
</s>
<s>
In	O
August	O
2012	O
,	O
Microsoft	O
renamed	O
Windows	B-Application
Phone	I-Application
Marketplace	I-Application
to	O
Windows	B-Application
Phone	I-Application
Store	I-Application
.	O
</s>
<s>
In	O
2015	O
,	O
Microsoft	O
announced	O
that	O
Windows	B-Application
Phone	I-Application
Store	I-Application
would	O
be	O
killed	O
out	O
and	O
replaced	O
by	O
Windows	B-Application
Store	I-Application
which	O
would	O
act	O
as	O
a	O
unified	O
store	O
for	O
all	O
Windows-powered	O
devices	O
.	O
</s>
<s>
This	O
process	O
was	O
complemented	O
by	O
the	O
Apps	O
on	O
Windows	O
website	O
,	O
an	O
interim	O
solution	O
before	O
the	O
unified	O
Windows	B-Application
Store	I-Application
.	O
</s>
<s>
Windows	B-Application
Phone	I-Application
Store	I-Application
supported	O
credit	O
card	O
purchases	O
,	O
operator	O
billing	O
,	O
and	O
ad-supported	O
content	O
.	O
</s>
<s>
Other	O
features	O
are	O
said	O
to	O
be	O
similar	O
to	O
Windows	B-Application
Phone	I-Application
Store	I-Application
's	O
predecessor	O
,	O
Windows	B-Operating_System
Marketplace	I-Operating_System
for	I-Operating_System
Mobile	I-Operating_System
.	O
</s>
<s>
The	O
Windows	B-Application
Phone	I-Application
Store	I-Application
had	O
61	O
categories	O
split	O
up	O
into	O
16	O
main	O
categories	O
and	O
25	O
sub-categories	O
.	O
</s>
<s>
Windows	B-Application
Phone	I-Application
Store	I-Application
also	O
featured	O
downloads	O
for	O
3D	O
games	O
that	O
will	O
have	O
integrated	O
Xbox	B-Application
Live	I-Application
connectivity	O
and	O
features	O
.	O
</s>
<s>
The	O
ability	O
to	O
download	O
a	O
XAP	B-Application
file	O
to	O
a	O
computer	O
was	O
also	O
present	O
,	O
allowing	O
a	O
user	O
to	O
install	O
an	O
app	O
from	O
their	O
SD	O
card	O
if	O
no	O
internet	O
access	O
was	O
available	O
.	O
</s>
<s>
Developers	O
had	O
to	O
pay	O
an	O
annual	O
subscription	O
fee	O
of	O
$99	O
to	O
become	O
an	O
App	O
Hub	O
member	O
and	O
submit	O
apps	O
to	O
the	O
Windows	B-Application
Phone	I-Application
Store	I-Application
.	O
</s>
<s>
This	O
,	O
according	O
to	O
Todd	O
Brix	O
,	O
the	O
General	O
Manager	O
for	O
Windows	B-Operating_System
Phone	I-Operating_System
Apps	I-Operating_System
and	O
Store	O
team	O
,	O
was	O
on	O
an	O
ongoing	O
promotion	O
at	O
$19	O
.	O
</s>
<s>
Developers	O
could	O
also	O
choose	O
to	O
work	O
with	O
OEMs	O
to	O
deploy	O
their	O
apps	O
;	O
this	O
would	O
allow	O
apps	O
to	O
be	O
preinstalled	O
on	O
Windows	B-Protocol
Phone	I-Protocol
devices	O
or	O
be	O
exclusive	O
to	O
that	O
specific	O
OEM	O
's	O
products	O
.	O
</s>
<s>
This	O
process	O
was	O
used	O
by	O
Microsoft	O
Mobile	O
(	O
formerly	O
Nokia	O
)	O
for	O
apps	O
specific	O
to	O
Lumia	B-Device
devices	O
(	O
including	O
Lumia	B-Device
Camera	O
,	O
HERE	B-Application
Maps	I-Application
,	O
and	O
MixRadio	B-Language
)	O
.	O
</s>
<s>
Most	O
Windows	B-Protocol
Phone	I-Protocol
OEMs	O
have	O
a	O
category	O
,	O
such	O
as	O
"	O
Lumia	B-Device
Collection	O
"	O
(	O
formerly	O
"	O
Nokia	O
Collection	O
"	O
)	O
,	O
"	O
Samsung	O
Zone	O
"	O
,	O
"	O
HTC	O
Apps	O
"	O
and	O
"	O
Huawei	O
Selected	O
"	O
for	O
this	O
purpose	O
.	O
</s>
<s>
A	O
user	O
could	O
download	O
games	O
and	O
apps	O
from	O
the	O
Windows	B-Application
Phone	I-Application
Store	I-Application
;	O
if	O
an	O
Xbox	B-Application
live	I-Application
account	O
is	O
enabled	O
,	O
the	O
store	O
could	O
be	O
accessed	O
remotely	O
from	O
the	O
phone	O
itself	O
.	O
</s>
<s>
Microsoft	O
had	O
lined	O
up	O
a	O
wide	O
range	O
of	O
popular	O
games	O
to	O
be	O
available	O
from	O
the	O
launch	O
of	O
Windows	B-Protocol
Phone	I-Protocol
7	O
.	O
</s>
<s>
Also	O
at	O
Gamescom	O
,	O
Microsoft	O
unveiled	O
more	O
than	O
50	O
premium	O
Windows	B-Protocol
Phone	I-Protocol
7	O
games	O
and	O
apps	O
that	O
used	O
the	O
Xbox	B-Application
Live	I-Application
mobile	O
connection	O
.	O
</s>
<s>
Windows	B-Application
Phone	I-Application
Store	I-Application
grew	O
swiftly	O
since	O
its	O
launch	O
and	O
by	O
February	O
2012	O
,	O
it	O
had	O
outgrown	O
Blackberry	O
App	O
World	O
with	O
70,000	O
apps	O
available	O
(	O
a	O
milestone	O
that	O
Blackberry	O
App	O
World	O
passed	O
in	O
March	O
2012	O
)	O
.	O
</s>
<s>
In	O
June	O
2012	O
,	O
after	O
20	O
months	O
,	O
Windows	B-Application
Phone	I-Application
Marketplace	I-Application
has	O
reached	O
100,000	O
apps	O
.	O
</s>
<s>
Windows	B-Application
Phone	I-Application
Store	I-Application
contained	O
more	O
than	O
300,000	O
apps	O
in	O
August	O
2014	O
.	O
</s>
<s>
Apps	O
in	O
Windows	B-Application
Phone	I-Application
Store	I-Application
are	O
subjected	O
to	O
a	O
content	O
policy	O
,	O
which	O
exists	O
to	O
guide	O
app	O
developers	O
,	O
and	O
to	O
facilitate	O
a	O
restriction	O
or	O
banning	O
of	O
certain	O
content	O
.	O
</s>
<s>
Suggestions	O
or	O
depictions	O
of	O
prostitution	O
,	O
sexual	O
fetishes	O
,	O
or	O
generally	O
anything	O
that	O
"	O
a	O
reasonable	O
person	O
would	O
consider	O
to	O
be	O
adult	O
or	O
borderline	O
adult	O
content	O
"	O
are	O
forbidden	O
from	O
the	O
marketplace	O
,	O
even	O
after	O
the	O
unification	O
with	O
Windows	B-Application
Store	I-Application
.	O
</s>
<s>
Windows	B-Protocol
Phone	I-Protocol
7	O
development	O
is	O
based	O
on	O
Silverlight	B-Application
,	O
XNA	B-Device
,	O
and	O
the	O
.NET	B-Operating_System
Compact	I-Operating_System
Framework	I-Operating_System
.	O
</s>
<s>
The	O
primary	O
tools	O
used	O
for	O
development	O
are	O
Visual	O
Studio	O
2010	O
and	O
Expression	B-Application
Blend	I-Application
.	O
</s>
<s>
Excluding	O
unlocked	O
developer	O
devices	O
,	O
Windows	B-Protocol
Phone	I-Protocol
7	O
only	O
runs	O
mobile	B-Application
apps	I-Application
that	O
have	O
first	O
been	O
approved	O
by	O
Microsoft	O
and	O
are	O
only	O
available	O
via	O
Windows	B-Application
Phone	I-Application
Store	I-Application
.	O
</s>
<s>
Apps	O
for	O
Windows	B-Protocol
Phone	I-Protocol
8	O
can	O
be	O
developed	O
either	O
in	O
native	O
code	O
or	O
managed	O
code	O
,	O
using	O
Visual	O
C#	O
,	O
Visual	B-Language
Basic	I-Language
.NET	I-Language
and	O
Visual	B-Application
C++	I-Application
.	O
</s>
<s>
Microsoft	O
has	O
deprecated	O
XNA	B-Device
in	O
favor	O
of	O
DirectX	B-Application
for	O
Windows	O
Runtime	O
.	O
</s>
<s>
The	O
phone	O
emulator	O
in	O
the	O
SDK	O
is	O
also	O
changed	O
to	O
use	O
Hyper-V	O
,	O
which	O
requires	O
at	O
least	O
Windows	O
8	O
Pro	O
or	O
Windows	B-Device
Server	I-Device
2012	I-Device
,	O
in	O
addition	O
to	O
hardware-assisted	B-General_Concept
virtualization	I-General_Concept
.	O
</s>
<s>
Finally	O
,	O
use	O
of	O
third-party	O
frameworks	O
such	O
as	O
Unity	B-Application
is	O
also	O
supported	O
.	O
</s>
<s>
For	O
a	O
time	O
,	O
developers	O
could	O
develop	O
Windows	B-Protocol
Phone	I-Protocol
7	O
apps	O
using	O
the	O
Windows	O
7	O
SDK	O
and	O
they	O
would	O
still	O
be	O
compatible	O
with	O
Windows	B-Protocol
Phone	I-Protocol
8	O
.	O
</s>
<s>
Windows	B-Operating_System
Phone	I-Operating_System
App	I-Operating_System
Studio	O
was	O
a	O
one	O
stop	O
source	O
for	O
rapid	O
app	O
building	O
for	O
Windows	B-Protocol
Phone	I-Protocol
.	O
</s>
<s>
With	O
a	O
couple	O
of	O
configuration	O
steps	O
(	O
complying	O
with	O
"	O
separation	O
of	O
concerns	O
"	O
)	O
,	O
users	O
can	O
generate	O
a	O
production-ready	O
app	O
for	O
Windows	B-Application
Store	I-Application
.	O
</s>
<s>
Once	O
all	O
the	O
configuration	O
and	O
look	O
and	O
feel	O
is	O
set	O
,	O
this	O
online	O
studio	O
let	O
you	O
publish	O
the	O
app	O
directly	O
to	O
Windows	B-Application
Phone	I-Application
Store	I-Application
.	O
</s>
<s>
Windows	B-Operating_System
Phone	I-Operating_System
App	I-Operating_System
Studio	O
makes	O
it	O
significantly	O
easy	O
for	O
non-developers	O
to	O
publish	O
homebrew	O
or	O
small	O
business	O
apps	O
without	O
indulging	O
them	O
in	O
source	O
code	O
or	O
hiring	O
a	O
developer	O
,	O
it	O
can	O
be	O
leveraged	O
as	O
a	O
starting	O
point	O
for	O
professional	O
developers	O
for	O
boilerplate	O
code	O
generation	O
.	O
</s>
<s>
Windows	B-Operating_System
Phone	I-Operating_System
App	I-Operating_System
Studio	O
was	O
later	O
renamed	O
to	O
Windows	B-Application
App	I-Application
Studio	O
which	O
serves	O
as	O
a	O
unified	O
app	O
studio	O
across	O
all	O
Windows	O
devices	O
.	O
</s>
<s>
In	O
Q2	O
2015	O
,	O
Microsoft	O
launched	O
Windows	B-Operating_System
10	I-Operating_System
Mobile	I-Operating_System
,	O
at	O
which	O
point	O
Windows	B-Application
Phone	I-Application
Store	I-Application
was	O
merged	O
with	O
Windows	B-Application
Store	I-Application
.	O
</s>
