[Nexus 7 Q&A, Help & Troubleshooting] NCSUZoSo:
A Few Apps For Battery Life

There are a couple things I would do, first is you need to monitor what is draining the battery. One thing to note though is your OC is obviously going to drain the battery quicker than stock and your governor setting could also affect this a lot. I am guessing your custom ROM has a non-stock kernel with it, if not I would recommend Franco's Kernel (r75 is the latest) and he even has an app that will keep you updated and flash for you (https://play.google.com/store/apps/details?id=com.franco.kernel&hl=en) there is also a free version of that. Franco's paid app has a built in power settings option that lets you adjust power usage per app that could be extremely useful in your case. However I would do some monitoring first and make sure a live wallpaper or a hardware monitor is not draining more battery than you think it is.

I've used these two apps and both do a great job of letting you know what is using the battery most during load/idle/sleep:

Better Battery Stats:

https://play.google.com/store/apps/details?id=com.asksven.betterbatterystats&hl=en

Go Power Master:

https://play.google.com/store/apps/details?id=com.gau.go.launcherex.gowidget.gopowermaster

Android Tuner (does A LOT for the price, including battery monitoring), If you are rooted this is almost a must buy:

https://play.google.com/store/apps/details?id=ccc71.at&hl=en

Also in Android Tuner and I think Better Battery Stats (I've uninstalled it since I got Android Tuner) there is an option to turn on a fast charge option. Fast Charge will decrease the time to charge the battery, however I haven't used this feature because it sounds like there must be a catch (more power to the battery quicker isn't going to be at stock spec power delivery from charger to battery). If my N7 was having trouble charging, I might consider it.

Really the first thing you need to do is install one of the monitoring apps and watch what is using your battery the most and if something is using it a lot that you didn't even realize. I was using UseMon to monitor and it was using 36% of my total battery usage, so I ditched it.

Then you have some things you can do to save your Battery

You have Juice Defender which has some great options in it if you are draining the battery too quickly:

https://play.google.com/store/apps/details?id=com.latedroid.juicedefender&hl=en

It comes in 3 versions Free, Plus and Ultimate.

One of my Favorites that saves the battery is Lux Dash:

https://play.google.com/store/apps/details?id=com.vito.lux&hl=en

There is also a free version, but this is easily worth the few bucks. It uses the camera to read the lighting of the environment you are in and based on the ratio you set, will dim or brighten your display. This method trumps any of the built in features, like NVIDIA's option.

Those two apps will help your battery a lot, especially if you also use the monitoring programs to see what is draining the battery so quickly.

You can read this article on some apps for monitoring and increasing battery life: http://reviews.cnet.com/8301-19736_...s-that-prolong-your-smartphones-battery-life/

and: http://www.talkandroid.com/guides/b...pps-for-analyzing-and-improving-battery-life/

Note these reviews/articles mention a lot of apps I have never tried nor mentioned, so be sure to read instructions on use carefully.

If this helped you at all please don't forget to give me a Thanks :D