I have an HP GPS charger. The electrical output is the same ( I think ) as Apple's own AC power adapter. However, I'm not so sure about the "input." Does the input charge matter? And what does input mean anyway? Here are my HP Charger's Specs: Input: 100-240V ~ 200mA 50-60Hz 12-17VA Output: +5V 1A Apple's iPod USB AC Adapter Specs: Input: 100-240V ~ 50/60 Hz 10A Output 5V- 1A So the differences are: My charger lists a 200mA for input, while Apple's doesn't list any. Mine says 12-17VA, while Apple's says 10A. Thank you! I've been addicted to my iPod touch since I received it for Christmas.