Contrary to what's been said about Apple's latest product, the iPhone will be able to offer up to 8 hours of talk time. Apple didn't cheat and turned off most of the hardware while testing the iPhone's battery life - the battery was tested with all default features turned on except for the Wi-Fi network scanner.

But that touchscreen sure looks like a power hog, so how did Apple do it?

Slate hypothesized that Apple may have tweaked the hardware. There's a little chance that batteries can be re-engineered to squeeze in more juice - but that's too much to ask even if we're talking about the powerful Lithium-ion types. Hardware can be subjected to a simple thing known as "power management".

Aside from the display screen, chips consume most amount of power when it comes to electronics. By collaborating with chip manufacturers, electronics companies can choose which chips to use that also use the least amount of power.

The iPhone's glass screen also plays a big part in conserving battery life; glass transmits brightness easily compared to the usual plastic, therefore using little amount of energy. In an effort to save lengthen battery life, more and more gadget manufacturers aside from Apple favor energy efficient displays, like light-emitting diode screens, against the conventional LCD displays.

Yet another way of saving energy is for the phone to shut down applications that are not being used. As we all know, the more applications are running, the more energy is expended. iPhone's version of the OS X is even programmed to regulate the phone's power usage, capable of powering down the processor just enough for the phone to support running programs.