I cannot get even close to 3 hours of screen on time.
My G2 saw 30 hours average with 2-2.5 hours screen on time and my G4 sees the same battery life between charges. I'd think the G3 would be similar.
I would suggest using the steps on our Battery drains fast page. It's got some helpful tips on how you can maximize your battery power so you can get the most out of it.
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