<s>
The	O
Nokia	B-Language
3650	I-Language
,	O
sold	O
in	O
North	O
American	O
markets	O
as	O
the	O
Nokia	O
3600	O
(	O
triband	O
GSM	O
850/1800/1900MHz	O
)	O
,	O
is	O
a	O
smartphone	B-Application
from	O
Nokia	O
announced	O
on	O
6	O
September	O
2002	O
as	O
the	O
successor	O
to	O
the	O
Nokia	B-Language
7650	I-Language
.	O
</s>
<s>
It	O
runs	O
Symbian	B-Operating_System
OS	I-Operating_System
Series	B-Language
60	I-Language
(	O
version	O
1.2	O
)	O
.	O
</s>
<s>
Many	O
owners	O
would	O
have	O
preferred	O
a	O
Series	B-Language
60	I-Language
device	O
with	O
a	O
conventional	O
keypad	O
,	O
however	O
some	O
stated	O
that	O
the	O
rotary	O
style	O
keypad	O
made	O
text	O
messaging	O
easier	O
and	O
faster	O
.	O
</s>
<s>
The	O
3600	O
was	O
the	O
first	O
Symbian	B-Operating_System
OS	I-Operating_System
device	O
to	O
appear	O
in	O
American	O
markets	O
.	O
</s>
<s>
By	O
that	O
time	O
the	O
business-oriented	O
Nokia	B-Language
6600	I-Language
was	O
released	O
as	O
the	O
company	O
's	O
flagship	O
Series	B-Language
60	I-Language
smartphone	B-Application
.	O
</s>
<s>
The	O
official	O
successor	O
to	O
the	O
3660	O
was	O
the	O
Nokia	B-Algorithm
3230	I-Algorithm
;	O
no	O
official	O
successor	O
was	O
released	O
for	O
the	O
3620	O
,	O
however	O
,	O
it	O
was	O
replaced	O
in	O
the	O
Cingular	O
Wireless	O
(	O
now	O
AT&T	O
Mobility	O
)	O
lineup	O
by	O
the	O
Nokia	B-Language
6620	I-Language
shortly	O
after	O
their	O
acquisition	O
of	O
AT&T	O
Wireless	O
Services	O
.	O
</s>
<s>
A	O
hardware	O
revision	O
of	O
the	O
3600	O
series	O
called	O
the	O
Nokia	B-Language
3660	I-Language
(	O
or	O
3620	O
in	O
North	O
America	O
)	O
,	O
was	O
announced	O
on	O
October	O
9	O
,	O
2003	O
to	O
replace	O
the	O
3600	O
and	O
3650	O
,	O
addressing	O
complaints	O
by	O
some	O
users	O
over	O
the	O
original	O
phone	O
's	O
circular	O
keypad	O
design	O
.	O
</s>
<s>
As	O
with	O
the	O
original	O
3600/3650	O
,	O
the	O
3620/3660	O
run	O
on	O
Series	B-Language
60	I-Language
version	O
1.x	O
on	O
Symbian	B-Operating_System
OS	I-Operating_System
.	O
</s>
<s>
Both	O
the	O
3620	O
and	O
3660	O
are	O
basically	O
the	O
same	O
phone	O
,	O
except	O
that	O
the	O
Nokia	B-Language
3620	I-Language
,	O
being	O
targeted	O
at	O
the	O
US	O
market	O
,	O
operates	O
on	O
GSM	O
850/1900	O
,	O
while	O
the	O
Nokia	B-Language
3660	I-Language
,	O
a	O
European	O
phone	O
,	O
operates	O
on	O
GSM	O
900/1800/1900	O
.	O
</s>
