Whenever you ran out of the power, it will start using the external battery power.
- When are you long away from the office or home, how you can give juice to your iPhone? It is easy, either bring a second iPhone Battery or have a Portable iPhone Charger Perfect solution to charge your iPhone when out, no need to worry about missing calls when iPhone is out of battery
- Useful 2000mAh iPhone Battery Extend, which has a much higher capacity than the iPhone’s 1400mAh internal iPhone Battery
Blue LED is showing charging state and capacity.