What is the battery life of iPod Touch (3G)? Is proper that when play music on it the battery percentage increases instead of discharge? I don't know if this is a fault or something. Again is it advisible to use insomnia on iPod?

Let me just clarify this... I think you meant 3rd generation iPod Touch? the "3G" there might cause ambiguity.

Anyway, the battery life of the 3rd gen iPod Touch is pretty good though not as good as the current one (obviously). Battery will supposedly drain when playing music but not that much. You can go for 24 hours of continuously playing music I guess.

If I understood correctly, you asked if playing music charges the battery and doesn't discharge. Well this is absolutely wrong. Everything you do on an ipod uses battery.
The only thing that really charges it is to use a charger.
Battery life decreases over time. So a new 3rd generation Ipod would have more battery life than a used one.
3G is for cell phones and requires a SIM card. I suppose you meant 3rd gen.
Hope this helps

Yes, I meant 3rd generation ipod. Thanks for your help