its limitations, TuneJuice will modestly extend the life of a well-charged iPod.

TuneJuice doesn't take advantage of the full capacity of its AAA batteries, and stops working when the batteries are about half-empty.

Pros - The TuneJuice 2 did help me watch movies on my iPhone during cross country flights

TuneJuice was the least effective and least convenient, but it did help somewhat

Also - because of the short cord, the TuneJuice made it uncomfortable to hold the iPhone during the flight.