Those battery saving apps are junk... like my friend down south here says, they pretty much fuss around with turning stuff on and off... which is something you can do, and with more control, with an automation app like Tasker or Llama.
Now, there are two apps/tools out there that WILL help you... Greenify and Amplify. The former 'hibernates' apps when not in use, keeping them from wasting power and the latter lets you control how your apps and services generate wakelocks (if you don't know what those are, learn). The two in tandem work a hell of a lot better than any of those battery saving apps in my expirience. But to get the most out of them, you need a rooted phone that can run the Xposed Framework (so no go on 5.0)