I nearly ditched my iphone 4 for a Blackberry because it had such a poor battery life and died every night if not left on charge. Then I came across this neat little case that doubles as a backup charger! A quick look around showed similar one at Amazon at £24.99 (albeit the 1700 mAh) model but for just over a fiver you can't go wrong.
Description from website below
Portable iPhone 4 Battery Case Features
Keep your iPhone 4 going for longer with our smart iPhone 4 Battery Case.
The high capacity 1500 mAh doubles your iPhone 4's run time, letting you talk, play and game for longer. Simply press the power on on the case when your iPhone is running low and the iPhone 4 Battery case will charge your phone.
Made from touch shell, with a soft rubberised coating means your iPhone is kept safe. Dedicated cutaways allow full access to your iPhone, with dedicates speaker and microphone grills, protection without compromise.
The status LED on the back of the iPhone 4 Battery Case lets you know instantly how much power is remaining, you choose to charge as much or as little as you like. The universal microUSB connector lets your charge your iPhone and Battery Case from any standard microUSB charger.
In the box:
- iPhone 4 Battery Case
- microUSB Cable Shipping Weight: 0.11kg