4. SpareOne Mobile Phone
SpareOne Mobile Phone
This phone comes from Xpal Power - the owners of both Energizer and Powerskin - so you don't get any points for guessing what they've focussed on. On just a single AA battery, this mobile can allegedly maintain its charge for up to 15 years. Obviously it's very basic, designed more for the glove compartment than the pocket but it could prove to be an interesting solution to contacting someone in an emergency.
Link: SpareOne Mobile Phone
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