Without its unsatisfying and hard-to-master keyboard and its inaccessible battery, the iPhone might have been the perfect gadget.

Without its unsatisfying and hard-to-master keyboard and its inaccessible battery, the iPhone might have been the perfect gadget.

Since the iPhone plays so many roles - telephone, personal media player, camera, pocket-size computer, and on-the-go connection to e-mail and the web - the inability to swap a spent battery for a fresh one when you're away from an electrical outlet can make for a very frustrating relationship between owner and gadget.

To help Alive readers avoid such iPhone frustrations, last October Gadget Spot featured the Mophie Juice Pack. That gadget is a hard-shell case for the iPhone and iPod Touch that acts as a second battery capable of doubling the life of your iPhone between charges.

Last week, Mophie started shipping the Juice Pack Air ($80 at mophie.com), a much improved and less costly successor to their original accessory. This particular product only works with an iPhone 3G.

To Mophie's credit, almost all of the shortcomings of their first product are corrected in the Juice Pack Air. My original Juice Pack had some kind of coating that started peeling off from day one. The Juice Pack Air is made of hard plastic with absolutely no coating.

The original Juice Pack was open at the top. On one unforgettable occasion, a friend shook my iPhone to activate an onboard app and my phone went flying from its case to a concrete floor (with no ill effect to the phone, which amazed both me and my former friend). The Juice Pack Air totally encases the iPhone 3G for added protection.

Once a user slid their iPhone into the original Juice Pack, the gadget's battery feature started to immediately charge the iPhone. The Juice Pack Air has its own power switch, so you can use it as a backup battery only when you need to.

The original Juice Pack only came in a single color - black. The Juice Pack Air is available in black, white or purple.

The USB cable supplied with the Juice Pack Air is cleverly designed to simultaneously charge itself and allow users to synch their iPhone 3G without having to remove it from the case.

The Juice Pack Air - which, like its predecessor, generally doubles the battery life of your iPhone 3G - is an accessory that takes the iPhone 3G one step closer to perfection.

Got a gadget question or a high-tech toy to recommend? E-mail gspot@columbusalive.com