We've seen several iPhone battery cases/extenders—and we've liked what we've seen. But offerings like the Fastmac iV have been a bit on the pudgy side.

The Mophie Juicepack Air is slated to be the sveltest iPhone battery boosting case yet. (Exactly how thin that means, we are honestly not sure.) Packed with a 1200 mAH lithium polymer battery, the Juicepack Air can function as a regular iPhone case, or it can be switched out of "standby" to add 4.5 hours of talk/surf time to the handset.

Priced at $80 and available this Spring, it might be alright, but now we're really craving a Capri Sun. That'll put the price up to $82.50 at least. [Mophie]

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