To help alleviate that situation, Sanwa Japan has introduced the 400-BT001. A rechargeable battery that adds around 3.5 hours to the iPhone operating talk time or around seven hours if you are using the handset for video play back or, alternatively, about 36 hours of audio.
The battery itself, according to the New Launches website, is a Lithium Ion and is rated at 1,200mAh. When purchased, the battery comes with a retractable USB cable plus an LED whch notifies you of the remaining battery life.
No UK distribution or price details have been announced but it is valued at around £25 equivalent.
Click to read the New Launches website