4. HTC Magnesium Unibody concept phone
Rybarczyk Francois has created this concept with battery life firmly in mind. The magnesium unibody of the smartphone allows you to slot an extra battery module into the back of the handset. This module can be pre-charged, or can charge whilst embedded in the phone via an AC charger. Even if the extra battery is not attached, the phone has a primary battery that works as normal. This idea is obviously not a new one, but the implementation is clean and stylish, and that is definitely a first.
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