When Apple introduced the second-generation iPod touch in 2008, it promised 36 hours of run time when playing back audio and doing nothing else—a claim both it and its 2009 third-generation sequel surpassed by nearly four hours. They used 2.92 Watt-Hour batteries at 3.7 volts, or roughly 789mAh. The fourth-generation iPod touch has just been revealed in photographs inside and out by the FCC, and surprise, there’s a 3.44 Watt-Hour battery…
