<s>
The	O
Psion	B-Application
Series	I-Application
5	I-Application
was	O
a	O
personal	B-Application
digital	I-Application
assistant	I-Application
(	O
PDA	B-Application
)	O
from	O
Psion	B-Application
.	O
</s>
<s>
It	O
came	O
in	O
two	O
main	O
variants	O
,	O
the	O
Series	O
5	O
(	O
launched	O
in	O
1997	O
)	O
and	O
the	O
Series	O
5mx	O
(	O
1999	O
)	O
,	O
the	O
latter	O
having	O
a	O
faster	O
processor	O
,	O
clearer	O
liquid	B-Device
crystal	I-Device
display	I-Device
(	O
LCD	B-Device
)	O
,	O
and	O
updated	O
software	O
.	O
</s>
<s>
There	O
was	O
also	O
a	O
rare	O
Series	O
5mx	O
Pro	O
,	O
which	O
differed	O
only	O
in	O
having	O
the	O
operating	B-General_Concept
system	I-General_Concept
(	O
OS	O
)	O
loaded	O
into	O
random-access	B-Architecture
memory	I-Architecture
(	O
RAM	B-Architecture
)	O
and	O
hence	O
upgradeable	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
5	I-Application
was	O
a	O
major	O
upgrade	O
from	O
the	O
Psion	B-Application
Series	I-Application
3	I-Application
.	O
</s>
<s>
A	O
Psion	B-Application
Series	O
4	O
does	O
not	O
exist	O
,	O
due	O
to	O
Psion	B-Application
's	O
concern	O
of	O
tetraphobia	O
in	O
their	O
Asian	O
markets	O
.	O
</s>
<s>
The	O
external	O
appearance	O
of	O
the	O
Psion	B-Application
Series	I-Application
5	I-Application
and	O
the	O
Psion	B-Application
Series	I-Application
5mx	I-Application
are	O
broadly	O
similar	O
,	O
but	O
their	O
mainboards	O
and	O
other	O
internal	O
components	O
were	O
different	O
and	O
not	O
interchangeable	O
.	O
</s>
<s>
The	O
Series	O
5	O
was	O
the	O
first	O
to	O
feature	O
a	O
unique	O
sliding	O
clamshell	O
design	O
,	O
whereby	O
the	O
keyboard	B-Device
slides	O
forward	O
as	O
the	O
device	O
opens	O
to	O
counterbalance	O
the	O
display	O
,	O
and	O
brace	O
it	O
such	O
that	O
touchscreen	B-Device
actuation	O
does	O
not	O
topple	O
the	O
device	O
,	O
a	O
feature	O
mentioned	O
in	O
the	O
granted	O
European	O
patent	O
EP	O
0766166B1	O
.	O
</s>
<s>
A	O
simplified	O
version	O
of	O
this	O
design	O
was	O
also	O
used	O
in	O
the	O
Psion	B-Application
Revo	I-Application
.	O
</s>
<s>
The	O
most	O
serious	O
common	O
problem	O
arose	O
because	O
of	O
a	O
design	O
fault	O
in	O
the	O
screen	O
cable	O
where	O
tooling	O
holes	O
caused	O
needless	O
stresses	O
due	O
to	O
extra	O
bending	O
of	O
the	O
cable	O
at	O
this	O
point	O
each	O
time	O
the	O
Psion	B-Application
Series	I-Application
5	I-Application
was	O
opened	O
or	O
closed	O
,	O
and	O
eventually	O
leading	O
to	O
failure	O
of	O
the	O
cable	O
,	O
which	O
caused	O
a	O
serious	O
display	O
malfunction	O
and	O
horizontal	O
lines	O
appearing	O
.	O
</s>
<s>
The	O
screen	O
cable	O
to	O
the	O
Psion	B-Application
Series	I-Application
5	I-Application
was	O
more	O
durable	O
than	O
the	O
screen	O
cable	O
of	O
the	O
Psion	B-Application
Series	I-Application
5mx	I-Application
.	O
</s>
<s>
At	O
its	O
heart	O
was	O
the	O
32-bit	O
ARM710-based	O
CL-PS7110	O
central	B-General_Concept
processing	I-General_Concept
unit	I-General_Concept
(	O
CPU	O
)	O
running	O
at	O
18MHz	O
(	O
Series	O
5	O
)	O
or	O
36MHz	O
(	O
5mx	O
)	O
,	O
with	O
4	O
,	O
8	O
,	O
or	O
16MB	O
of	O
RAM	B-Architecture
.	O
</s>
<s>
It	O
was	O
powered	O
by	O
two	O
AA	B-Algorithm
batteries	I-Algorithm
,	O
typically	O
giving	O
10	O
–	O
20	O
hours	O
of	O
use	O
.	O
</s>
<s>
The	O
display	O
is	O
a	O
touch-sensitive	B-Device
,	O
backlit	O
half-Video	O
Graphics	O
Array	O
(	O
VGA	B-Protocol
,	O
pixel	B-Algorithm
)	O
LCD	B-Device
with	O
16	O
greyscales	O
.	O
</s>
<s>
The	O
keyboard	B-Device
,	O
which	O
has	O
a	O
key-pitch	O
of	O
12.5mm	O
,	O
is	O
generally	O
considered	O
to	O
be	O
amongst	O
the	O
best	O
for	O
its	O
size	O
,	O
with	O
large-travel	O
keys	O
and	O
touch-type	O
capability	O
.	O
</s>
<s>
A	O
speaker	O
and	O
microphone	B-Application
were	O
also	O
provided	O
,	O
giving	O
dictation	O
as	O
well	O
as	O
music	O
playing	O
ability	O
.	O
</s>
<s>
External	O
storage	O
was	O
on	O
CompactFlash	B-Device
.	O
</s>
<s>
The	O
EPOC	B-Language
operating	B-General_Concept
system	I-General_Concept
,	O
since	O
renamed	O
Symbian	B-Operating_System
OS	I-Operating_System
,	O
was	O
built-in	O
,	O
along	O
with	O
application	B-Application
software	I-Application
including	O
a	O
word	B-General_Concept
processor	I-General_Concept
,	O
spreadsheet	B-Application
,	O
database	O
,	O
email	O
,	O
contact	O
and	O
diary	O
manager	O
,	O
and	O
Psion	B-Application
's	O
Open	B-Language
programming	I-Language
language	I-Language
(	O
OPL	O
)	O
for	O
developing	O
software	O
.	O
</s>
<s>
A	O
Java	B-Language
virtual	I-Language
machine	I-Language
,	O
the	O
mobile	B-Application
browser	I-Application
STNC	O
HitchHiker	O
and	O
synchronizing	O
software	O
for	O
Microsoft	B-Application
Windows	I-Application
was	O
bundled	O
with	O
the	O
5mx	O
as	O
optional	O
installations	O
and	O
,	O
later	O
,	O
the	O
Executive	O
Edition	O
of	O
the	O
5mx	O
was	O
bundled	O
with	O
various	O
hardware	O
and	O
software	O
extras	O
including	O
version	O
3.62	O
of	O
the	O
Opera	B-Application
web	I-Application
browser	I-Application
and	O
a	O
mains	O
electric	O
outlet	O
adapter	O
.	O
</s>
<s>
A	O
wealth	O
of	O
third-party	O
software	O
was	O
also	O
available	O
,	O
including	O
games	O
,	O
utilities	O
,	O
navigation	O
,	O
reference	O
,	O
communication	O
,	O
and	O
productivity	O
applications	O
,	O
and	O
standard	O
programming	O
tools	O
like	O
Perl	B-Language
and	O
Python	B-Language
.	O
</s>
<s>
An	O
open-source	B-Application
software	I-Application
project	O
,	O
OpenPsion	O
,	O
formerly	O
PsiLinux	O
,	O
supports	O
Linux	B-Application
on	O
the	O
Psion	B-Application
5mx	I-Application
and	O
other	O
Psion	B-Application
PDAs	B-Application
.	O
</s>
<s>
Psion	B-Application
's	O
experience	O
designing	O
for	O
this	O
form	O
factor	O
and	O
attention	O
to	O
detail	O
made	O
these	O
machines	O
a	O
favourite	O
with	O
power	O
users	O
,	O
many	O
of	O
whom	O
kept	O
using	O
them	O
,	O
despite	O
their	O
age	O
and	O
the	O
appearance	O
of	O
Symbian	B-Operating_System
OS	I-Operating_System
for	O
mobile	O
phones	O
and	O
other	O
PDAs	B-Application
with	O
more	O
impressive	O
specifications	O
.	O
</s>
<s>
In	O
2017	O
,	O
a	O
team	O
of	O
original	O
Psion	B-Application
engineers	O
created	O
a	O
startup	O
company	O
,	O
Planet	O
Computers	O
,	O
to	O
make	O
an	O
Android	B-Application
device	O
in	O
a	O
similar	O
form	O
factor	O
,	O
the	O
Gemini	B-Application
(	O
PDA	B-Application
)	O
.	O
</s>
<s>
The	O
Cosmo	O
Communicator	O
is	O
a	O
development	O
of	O
this	O
device	O
,	O
enhancements	O
including	O
an	O
external	O
touchscreen	B-Device
on	O
the	O
rear	O
of	O
the	O
clamshell	O
lid	O
,	O
mainly	O
to	O
facilitate	O
use	O
as	O
a	O
mobile	O
phone	O
without	O
opening	O
.	O
</s>
