Lumia 820 - I can kill my battery in 4-5 hrs with heavy use. Moderate use I can get 9-10 hrs. If I'm really careful with light use, I can get 16-18 hrs.
^^^^how much do you use the 510 for it to last you 4-7 days Jay ?
Lumia 620. 7 hours on casual web browsing.
I've noticed the same thing with this 1020. There are days I don't use the phone much and battery life is terrible and days I can make a bunch of calls and stuff and still have tons of battery left. Now I do feel some days it's because my phone is switching to a 4g tower that I only can get on somedays here at the house and some days I don't see it switching. If I would try the trick I've seen posted to force it not to look for a 4g signal I think it would help but there are other things I just can't use to on the 1020 so I just want to sell it and not worry about. Trouble is so many are going to non removable batteries that it gets harder to find themThere appears to be no logic to my 920's battery life. I'll have days I don't use it and it has super, incredible, amazingly fast, massive drain. Then other days with heavy usage the battery life is great.
Has your battery life increased or decreased after amber update?
Lumia 720. ~2 days with heavy usage, and upto 4 with light to med usage. It really depends on what you're doing with it. But the battery on 720 is excelent imo.