Mophie Power Devices/Batteries

The Bottom Line: If its Micro-USB port doesn't put you off, the Juice Pack Air works well both as a protective case and as a supplemental battery for the iPhone 3G.

Specs: Lithium polymer, 2.5 in x 0.9 in x 4.8 in

The Bottom Line: If its Micro-USB port doesn't put you off, the Juice Pack Air works well both as a protective case and as a supplemental battery for the iPhone 3G.

The Bottom Line: If its Micro-USB port doesn't put you off, the Juice Pack Air works well both as a protective case and as a supplemental battery for the iPhone 3G.

The Bottom Line: If you can get over its bulk and price, the Mophie Juice Pack will indeed extend the battery life of your iPhone 3G.

Specs: Lithium polymer, 2.5 in x 0.7 in x 4.8 in

The Bottom Line: The Juice Pack comes at a high price for a glorified battery, but weary, entertainment-starved travelers will appreciate the extra time it offers.

Specs: 24 hour(s), Lithium polymer

Specs: Lithium polymer, 2.6 in x 0.7 in x 4.8 in

Specs: Lithium polymer, 2.6 in x 0.9 in x 4.8 in