The most common criticism is that the phone is slow after an upgrade. There are also many complaints that the phone drains the battery quickly and becomes excessively hot. Concern about general problems such as slowness and battery life on gadgets isn't unusual, but using iOS 4 on the iPhone 3G seems to make the problems so bad that the phone is nearly unusable for some people.
for iPhone 3G due to hardware limitations so it was disappointing (more…)

The “coma mode” problem was a strange issue. Many iPhone users had complained thatafter upgrading to iPhone OS 3.1 their iPhone sometimes did not respond from the sleep mode and the only option they had to bring it back to life was to hard reboot it. In fact, many users felt that the iPhone had randomly shutdown.
The good news is that Apple has confirmed that the “coma mode” bug has been fixed in iPhone OS 3.1.2 and are advising users to (more…)