External Batteries and the 4S

[iPhoneApple]

Hi,
Do you think it would be necessary to have an external battery for the iPhone 4s? I noticied mophie is having a sale on their battery packs and wanted to know if they are that useful.

 

[DougNg]

I travel a lot for work, so i keep a NewTrent iDual handy when I do. I don't need an external battery all the time, so the Mophie is just added bulk I don't always need

Combined with some Griffin mini cables, it keeps my charging needs under control (iPhone, Blackberry, e-cigarettes and bluetooth device)