Nokia 3660/3620 A hardware revision of the 3600 series called the Nokia 3660 (or 3620 in North America), was announced on October 9, 2003 to replace the 3600 and 3650, addressing complaints by some users over the original phone's circular keypad design. As with the original 3600/3650, the 3620/3660 run on Series 60 version 1.x on Symbian OS. Changes from the 3600/3650 include a conventional keypad (as opposed to the 3650's circular keypad), and a 16-bit display (as opposed to the 3650's 12-bit display). Both the 3620 and 3660 are basically the same phone, except that the Nokia 3620, being targeted at the US market, operates on
GSM 850/1900, while the Nokia 3660, a European phone, operates on GSM 900/1800/1900. ==References==