Actually 1 trick worked miracles for me: Disable/Uninstall Chrome browser. That thing is a battery hog. The phone used to get so hot and sometimes it would actually overheat, after a few minutes of use.

I defaulted back to Opera Mini. Save for a few sites that it doesn't render very well, this worked for me. For the sites that don't display well, there are apps. Think FB, LinkedIn, etc.

If you have a rooted phone, I saw guys recommending the AOSP browser. Or even Firefox.

Thing with Chrome is that it drains the battery even when it's not in use.

Tip no. 2: I use AVG which I think takes this work a little bit too seriously. At 30% it kills all my connections, reduces brightness (and a few other battery optimizations)

Sources:

My experience - My phone is now at 26%, 16hrs after I disconnected the charger at 73%