It has been speculated until now that the future iPhone would have a larger screen and everyone seems to agree with this change that Apple would prepare. Many have said that the change is made to make the iPhone a bit more competitive in front of other Android smartphones, but it could be related to the battery of the terminal. David Progue of the New York Times says that the next iPhone will have a larger screen and a modified design because Apple would like to implement a larger capacity battery in the iPhone 5.
Somewhere along the line, I remember somebody at Apple telling me why there wasn't a 4G LTE iPhone — a phone capable of getting onto the superfast cellular networks sprouting up in major cities. And the reason was battery life. The 4G circuitry of the time (a couple of years ago) drew so much power, the battery would be depleted unacceptably quickly. For proof, all you have to do is look at 4G Android phones, whose batteries generally don't last even a full day. So I'm guessing that the iPhone's upsizing will be equally necessary to accommodate a bigger battery, so that Apple can solve the 4G/dead battery issue.
He says that the implementation of compatibility with 4G networks would require the implementation of a larger capacity battery that would also have larger dimensions, thus giving birth to the iPhone with a 4-inch screen. His theory is correct because in the iPad 3 Apple has implemented an almost double capacity battery to support the Retina Display and the 4G/LTE chip, and the same could happen with the iPhone 5. According to Apple it could claims that the autonomy of the new iPhone is as good as that of the iPhone 4S, but this is not so great considering that the current iPhone does not have an autonomy that great.
