<s>
The	O
Psion	B-Application
Series	I-Application
3	I-Application
range	O
of	O
personal	B-Application
digital	I-Application
assistants	I-Application
were	O
made	O
by	O
Psion	B-Application
PLC	I-Application
.	O
</s>
<s>
The	O
four	O
main	O
variants	O
are	O
the	O
Psion	B-Application
Series	I-Application
3	I-Application
(	O
1991	O
)	O
,	O
the	O
Psion	B-Application
Series	I-Application
3a	I-Application
(	O
1993	O
)	O
,	O
the	O
Psion	B-Application
Series	I-Application
3c	I-Application
(	O
1996	O
)	O
,	O
and	O
the	O
Psion	B-Application
Series	I-Application
3mx	I-Application
(	O
1998	O
)	O
,	O
all	O
sized	O
.	O
</s>
<s>
Further	O
,	O
a	O
Psion	B-Application
Series	I-Application
3a	I-Application
variant	O
with	O
factory	O
installed	O
software	O
for	O
the	O
Russian	O
language	O
was	O
called	O
a	O
Psion	B-Application
Series	O
3aR	O
,	O
and	O
Acorn	O
Computers	O
sold	O
renamed	O
versions	O
of	O
the	O
Psion	B-Application
Series	I-Application
3	I-Application
and	O
3a	O
marketed	O
as	O
the	O
Acorn	O
Pocket	O
Book	O
and	O
Acorn	O
Pocket	O
Book	O
II	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3	I-Application
range	O
was	O
regarded	O
in	O
2009	O
by	O
writer	O
Charles	O
Stross	O
as	O
an	O
unsurpassed	O
PDA	B-Application
because	O
of	O
its	O
long	O
battery	O
life	O
(	O
20	O
to	O
35	O
hours	O
)	O
,	O
its	O
stable	O
and	O
versatile	O
software	O
,	O
and	O
its	O
durable	O
hardware	B-Architecture
.	O
</s>
<s>
Others	O
describe	O
over	O
twenty	O
years	O
of	O
daily	O
use	O
with	O
models	O
such	O
as	O
the	O
Psion	B-Application
3mx	O
.	O
</s>
<s>
About	O
1.5	O
million	O
Psion	B-Application
3s	I-Application
were	O
made	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3	I-Application
models	O
were	O
a	O
major	O
advance	O
on	O
the	O
Psion	B-Application
Organiser	I-Application
.	O
</s>
<s>
Manufacture	O
of	O
Psion	B-Application
3s	I-Application
was	O
discontinued	O
in	O
1998	O
shortly	O
after	O
the	O
launch	O
of	O
the	O
Psion	B-Application
Series	I-Application
5	I-Application
(	O
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
and	O
the	O
Psion	B-Application
Siena	I-Application
.	O
</s>
<s>
Psion	B-Application
's	O
industrial	O
hardware	B-Architecture
division	O
continue	O
to	O
produce	O
handhelds	O
running	O
the	O
same	O
16-bit	B-Device
operating	O
system	O
,	O
some	O
17	O
years	O
after	O
its	O
introduction	O
on	O
the	O
Psion	B-Application
MC	O
range	O
of	O
laptops	O
and	O
5	O
years	O
after	O
Psion	B-Application
Computer	O
's	O
final	O
32-bit	O
EPOC	B-Language
PDA	B-Application
was	O
released	O
.	O
</s>
<s>
All	O
Series	O
3	O
variants	O
are	O
powered	O
by	O
two	O
AA	B-Algorithm
battery	I-Algorithm
cells	O
which	O
are	O
easily	O
obtainable	O
,	O
rather	O
than	O
having	O
a	O
specially	O
shaped	O
proprietary	O
battery	O
which	O
are	O
often	O
difficult	O
to	O
replace	O
.	O
</s>
<s>
All	O
have	O
an	O
internal	O
backup	O
battery	O
in	O
the	O
form	O
of	O
an	O
easily	O
changed	O
small	O
button	O
cell	O
,	O
which	O
allows	O
the	O
main	O
AA	B-Algorithm
batteries	I-Algorithm
to	O
be	O
changed	O
while	O
losing	O
no	O
data	O
files	O
.	O
</s>
<s>
The	O
Series	O
3	O
's	O
innovative	O
clamshell	O
design	O
did	O
have	O
some	O
problems	O
:	O
breakages	O
of	O
any	O
of	O
the	O
four	O
hinges	O
;	O
loss	O
of	O
function	O
in	O
the	O
button	O
bar	O
between	O
the	O
two	O
halves	O
of	O
the	O
clam	O
;	O
and	O
deterioration	O
of	O
the	O
cable	O
linking	O
the	O
keyboard	B-Device
half	O
to	O
the	O
screen	O
,	O
leading	O
to	O
a	O
serious	O
display	O
problem	O
with	O
vertical	O
lines	O
appearing	O
.	O
</s>
<s>
Psion	B-Application
Series	I-Application
3s	I-Application
have	O
room	O
for	O
two	O
flash-memory	O
cards	O
,	O
which	O
enabled	O
backup	O
of	O
data	O
.	O
</s>
<s>
Psion	B-Application
,	O
Acorn	O
and	O
third	O
party	O
software	O
was	O
available	O
loaded	O
onto	O
such	O
memory	O
cards	O
which	O
were	O
available	O
as	O
separate	O
packs	O
.	O
</s>
<s>
The	O
tone	O
dialing	O
feature	O
was	O
integrated	O
into	O
the	O
Psion	B-Application
's	O
Agenda	O
,	O
Contacts	O
and	O
Data	O
applications	O
.	O
</s>
<s>
One	O
unique	O
feature	O
of	O
the	O
Psion	B-Application
Series	I-Application
3	I-Application
software	O
package	O
was	O
a	O
built-in	O
programming	O
language	O
,	O
Organiser	O
then	O
Open	B-Language
Programming	I-Language
Language	I-Language
(	O
OPL	O
)	O
,	O
which	O
enabled	O
users	O
to	O
create	O
their	O
own	O
applications	O
that	O
ran	O
and	O
looked	O
just	O
as	O
system	O
programs	O
.	O
</s>
<s>
This	O
,	O
along	O
with	O
the	O
rise	O
in	O
popularity	O
of	O
forums	O
such	O
as	O
Compuserve	O
and	O
CIX	O
,	O
led	O
to	O
a	O
significant	O
shareware	B-License
scene	O
,	O
(	O
still	O
)	O
archived	O
by	O
Steve	O
Litchfield	O
and	O
the	O
3-Lib	O
shareware	B-License
library	O
,	O
begun	O
in	O
1994	O
.	O
</s>
<s>
This	O
Psion	B-Application
shareware	B-License
scene	O
was	O
mirrored	O
a	O
few	O
years	O
later	O
by	O
the	O
PalmPilot	B-Device
shareware	B-License
scene	O
and	O
both	O
were	O
forerunners	O
of	O
the	O
'	O
app'-centric	O
mobile	O
market	O
that	O
exists	O
today	O
.	O
</s>
<s>
The	O
Embeddable	B-Application
Linux	I-Application
Kernel	I-Application
Subset	I-Application
project	O
has	O
produced	O
a	O
small	O
subset	O
of	O
Linux	B-Application
that	O
runs	O
on	O
the	O
Series	O
3a	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3	I-Application
was	O
the	O
first	O
truly	O
useful	O
personal	B-Application
digital	I-Application
assistant	I-Application
(	O
PDA	B-Application
)	O
.	O
</s>
<s>
Besides	O
the	O
agenda	O
with	O
multiple	O
views	O
,	O
it	O
featured	O
a	O
database	O
,	O
a	O
word	B-General_Concept
processor	I-General_Concept
,	O
a	O
spreadsheet	B-Application
with	O
charts	O
,	O
world	O
times	O
,	O
and	O
more	O
.	O
</s>
<s>
With	O
an	O
optional	O
modem	B-Application
,	O
it	O
could	O
connect	O
to	O
the	O
Internet	O
for	O
very	O
basic	O
web	O
browsing	O
and	O
email	O
functionality	O
through	O
the	O
official	O
Psi	O
Mail	O
app	O
.	O
</s>
<s>
It	O
could	O
be	O
programmed	O
in	O
Organiser	B-Language
Programming	I-Language
Language	I-Language
(	O
OPL	O
)	O
,	O
with	O
easy	O
access	O
to	O
menu	O
and	O
computer	O
graphics	O
functions	O
.	O
</s>
<s>
The	O
hardware	B-Architecture
was	O
the	O
same	O
as	O
the	O
Series	O
3	O
,	O
but	O
the	O
integrated	O
applications	O
were	O
different	O
;	O
for	O
example	O
,	O
the	O
Pocket	O
Book	O
omitted	O
the	O
Agenda	O
diary	O
application	O
,	O
which	O
became	O
an	O
optional	O
install	O
from	O
floppy	O
diskette	O
.	O
</s>
<s>
The	O
most	O
obvious	O
upgrade	O
to	O
the	O
Psion	B-Application
3a	I-Application
is	O
a	O
larger	O
screen	O
,	O
now	O
67%	O
larger	O
than	O
the	O
screen	O
found	O
on	O
the	O
Series	O
3	O
.	O
</s>
<s>
Another	O
significant	O
upgrade	O
was	O
to	O
the	O
audio	O
capabilities	O
,	O
introducing	O
the	O
audio	O
recording	O
and	O
playback	O
capabilities	O
demonstrated	O
by	O
the	O
Psion	B-Operating_System
MC	I-Operating_System
series	I-Operating_System
,	O
although	O
no	O
compression	O
was	O
performed	O
on	O
recorded	O
audio	O
which	O
would	O
consume	O
8KB	O
of	O
memory	O
per	O
second	O
.	O
</s>
<s>
The	O
Series	O
3a	O
has	O
a	O
NEC	B-Device
V30H	I-Device
CPU	O
(	O
running	O
at	O
7.68MHz	O
and	O
thereby	O
twice	O
as	O
fast	O
as	O
the	O
Series	O
3	O
)	O
,	O
a	O
microphone	O
for	O
voice	O
recording	O
,	O
an	O
input/output	B-General_Concept
(	O
I/O	B-General_Concept
)	O
port	O
(	O
for	O
modem	B-Application
,	O
printing	O
and	O
PC	O
synchronization	O
)	O
,	O
and	O
256	O
kB	O
,	O
512	O
kB	O
,	O
1	O
MB	O
or	O
2	O
MB	O
of	O
random-access	B-Architecture
memory	I-Architecture
(	O
RAM	B-Architecture
)	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3a	I-Application
range	O
was	O
revised	O
in	O
1995	O
to	O
include	O
models	O
with	O
1	O
MB	O
or	O
2	O
MB	O
of	O
RAM	B-Architecture
and	O
more	O
software	O
was	O
factory	O
preloaded	O
into	O
the	O
ROM	B-Device
.	O
</s>
<s>
This	O
included	O
a	O
spell	O
checker	O
and	O
thesaurus	O
,	O
communication	O
software	O
,	O
games	O
and	O
more	O
,	O
though	O
all	O
of	O
these	O
had	O
been	O
available	O
formerly	O
as	O
optional	O
extras	O
(	O
or	O
in	O
the	O
case	O
of	O
the	O
comms	O
software	O
,	O
as	O
a	O
program	O
loaded	O
from	O
the	O
ROM	B-Device
of	O
the	O
3Link	O
serial	B-Protocol
connector	I-Protocol
)	O
for	O
earlier	O
models	O
.	O
</s>
<s>
This	O
added	O
back	O
some	O
of	O
the	O
applications	O
omitted	O
from	O
the	O
original	O
Pocket	O
Book	O
,	O
so	O
was	O
closer	O
in	O
specification	O
to	O
the	O
standard	O
Psion	B-Application
model	O
.	O
</s>
<s>
For	O
example	O
,	O
Psion	B-Application
's	O
Agenda	O
application	O
was	O
replaced	O
,	O
although	O
renamed	O
Schedule	O
,	O
and	O
a	O
new	O
Plotter	O
application	O
(	O
graph-plotting	O
software	O
)	O
was	O
added	O
.	O
</s>
<s>
There	O
was	O
also	O
a	O
modification	O
of	O
the	O
Series	O
3a	O
for	O
the	O
Russian	O
market	O
named	O
Psion	B-Application
Series	O
3aR	O
,	O
which	O
had	O
software	O
factory	O
installed	O
directly	O
in	O
the	O
read-only	B-Device
memory	I-Device
(	O
ROM	B-Device
)	O
for	O
the	O
Russian	O
language	O
.	O
</s>
<s>
All	O
the	O
other	O
Series	O
3	O
models	O
had	O
software	O
for	O
the	O
English	O
language	O
factory	O
installed	O
and	O
localization	B-General_Concept
required	O
installation	O
of	O
localization	B-General_Concept
software	O
,	O
which	O
was	O
bundled	O
in	O
the	O
box	O
with	O
the	O
Psion	B-Application
palmtop	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3c	I-Application
was	O
the	O
next	O
variant	O
after	O
the	O
Psion	B-Application
Series	I-Application
3a	I-Application
.	O
</s>
<s>
(	O
A	O
Psion	B-Application
Series	O
3b	O
does	O
not	O
exist	O
)	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3mx	I-Application
was	O
the	O
last	O
upgrade	O
in	O
the	O
popular	O
16-bit	B-Device
(	O
SIBO	O
)	O
Series	O
3	O
line	O
.	O
</s>
<s>
Announced	O
in	O
July	O
1998	O
,	O
after	O
the	O
release	O
of	O
the	O
32-bit	O
(	O
EPOC	B-Language
)	O
Psion	B-Application
Series	I-Application
5	I-Application
,	O
the	O
3mx	O
is	O
essentially	O
an	O
upgraded	O
Series	O
3c	O
.	O
</s>
<s>
The	O
Psion	B-Application
Series	I-Application
3mx	I-Application
and	O
Series	O
3c	O
have	O
a	O
similar	O
overall	O
external	O
appearance	O
,	O
except	O
the	O
3mx	O
sports	O
a	O
matte	O
silver	O
metallic	O
paint	O
covering	O
,	O
rather	O
than	O
the	O
dark	O
grey	O
finish	O
of	O
the	O
3c	O
.	O
</s>
<s>
The	O
Series	O
3mx	O
has	O
a	O
faster	O
processor	O
:	O
a	O
16	B-Device
bit	I-Device
NEC	O
V30MX	O
(	O
80C86	O
compatible	O
)	O
running	O
at	O
27.684MHz	O
,	O
and	O
a	O
faster	O
RS232c	O
connection	O
,	O
which	O
was	O
boosted	O
to	O
115	O
kbit/s	O
.	O
</s>
<s>
The	O
Series	O
3mx	O
takes	O
a	O
CR2025	O
backup	O
battery	O
which	O
is	O
larger	O
than	O
the	O
CR1620	O
that	O
is	O
used	O
for	O
the	O
previous	O
series	O
3	O
Psion	B-Application
models	O
.	O
</s>
<s>
The	O
ability	O
to	O
browse	O
the	O
World	O
Wide	O
Web	O
on	O
the	O
device	O
was	O
also	O
available	O
through	O
the	O
STNC	O
HitchHiker	O
mobile	B-Application
browser	I-Application
,	O
although	O
it	O
was	O
only	O
available	O
for	O
use	O
with	O
an	O
external	B-Application
modem	I-Application
.	O
</s>
<s>
Software	O
was	O
available	O
from	O
Psion	B-Application
PLC	I-Application
or	O
from	O
third	O
parties	O
,	O
such	O
as	O
Purple	O
Software	O
,	O
PsionPages	O
or	O
Widget	O
UK	O
.	O
</s>
<s>
A	O
Mob-i-Mail	O
software	O
package	O
was	O
used	O
to	O
enable	O
sending	O
email	O
via	O
Short	O
Message	O
Service	O
(	O
SMS	B-Device
)	O
and	O
Mobitext	O
networks	O
.	O
</s>
<s>
The	O
older	O
RAM	B-Architecture
needed	O
a	O
button	O
cell	O
to	O
keep	O
the	O
data	O
stable	O
in	O
the	O
memory	O
.	O
</s>
<s>
This	O
made	O
the	O
RAM	B-Architecture
modules	O
more	O
desirable	O
for	O
use	O
where	O
the	O
data	O
stored	O
was	O
likely	O
to	O
be	O
changed	O
frequently	O
,	O
as	O
every	O
change	O
with	O
a	O
flash	O
module	O
meant	O
writing	O
a	O
new	O
version	O
of	O
the	O
file	O
into	O
the	O
remaining	O
space	O
.	O
</s>
<s>
The	O
Psion	B-Application
Travel	O
Modem	B-Application
is	O
an	O
optional	O
extra	O
.	O
</s>
<s>
They	O
were	O
made	O
at	O
the	O
Psion	B-Application
Dacom	O
plc	O
factory	O
in	O
Milton	O
Keynes	O
,	O
England	O
.	O
</s>
<s>
The	O
connections	O
to	O
the	O
Psion	B-Application
Series	I-Application
3	I-Application
and	O
3a	O
are	O
different	O
from	O
those	O
for	O
the	O
Series	O
3c	O
and	O
3mx	O
.	O
</s>
