After 3 weeks of use, I notice that the battery seems to slowly last a little longer than the first week. Now, mine can definitely last for 20 hours and even more! That's with moderate usage, constant WhatsApp, Facebook, Twitter, web browsing, all-time WiFi (I switched off the 'turn off WiFi when screen times out'), and many more. Pretty much like how you use your smartphone.
1300 mah is small, I was concerned of its battery life at first and thought of getting a power bank but I honestly never thought it could last this long. It's typical nowadays that smartphones last for a day and some even less. I held a test 2 weeks ago with my friends Lumia 800, 900, Samsung Galaxy S3, Note and iPhone 4S, take note it was 2 weeks ago and as mentioned by
Tiwo, mine can easily last between 15-24 hours while the other competitors struggle with exactly the same use. That's not valid anymore though, now I can get it to last for more than 20 hours
Just last week, it started to last a day and here's what I get last week:
View attachment 28444
22 hours, plus exactly one more hour to spend, a total of 23 hours. Two days ago, I managed to pull a total of 1 day and 18 hours but didn't capture the screenshot though. I used to use the battery saver feature but now, I don't need it anymore. I won't say this phone has got an excellent battery but it's good enough considering that it comes in a very well priced package. I couldn't ask for more, really. If I ever get to see a bigger battery pack here, I will definitely go for it. It's like putting a bigger tank in your car!
EDIT: But if you're the kind of user that's just going to stick on the phone for 24/7 and needed a very good battery life, this is not the phone though. Definitely. Haha!