How to odex your ROM for better battery life and performance

Over the past few days, I’ve kept my Crack Flashing habit at bay by installing numerous Jelly Bean leaks and other custom ROM’s on my Samsung Galaxy S III. For the most part, these ROM’s are deodexed.

If you’re not familiar with the term, .apk files have respective odexes that devs use to “supposedly” save space. Deodexing means you convert it back to a .dex file and put it back inside the apk.

This allows you to easily replace files (not having to worry about odexes), but the main point is to deodex services.jar so that you can change all text to different colors (such as the clock color to white) and to deodex services.jar, you need to deodex everything.

In English, this basically opens up the field for themers and modders to do their thing, but deodexed ROM’s do come with a downside — they’re a bit slower and consume a bit more battery life than if the ROM was fully odexed.

If you happen to be running a deodexed ROM and would like to convert it to odexed, it’s a very simple process, thanks to well-known Android developer, Paul O’Brien, of MoDaCo fame.

Last month, Paul released an application called, Deodex Me, which does exactly as the title implies — deodexes your ROM. The end result: better battery life and performance for you.

It’s important to note that odexing your /system/data means you can’t make any /system/framework changes, but how often do you need to do that? If you DO need to, you can reflash your ROM, do the changes, then run OdexMe again. Simple as pie.

Now for the juicy deetz.

This will work on ANY DEODEXED ROM, I’m compiling a list of confirmed ones however for you guys that are weary of this.

*Use this only AFTER you’ve made any changes to the framework or flashed .zips that change the framework.*

First and foremost, make a backup! You should always do this before messing with system files!

1) Make sure you have a rooted rom, without root the app won’t do much but install.
2) Allow “Unknown sources” by going into Settings > Security > and scroll down.
3) Download the .apk either down below, or from the link above.
4) Install as a normal app.
5) Open the app, make sure you give it root access, and it will run.
6) Let it run, it will reboot your phone, take around 5-10 minutes, and then reboot again. You will be greeted by “Android is upgrading” which means its rebuilding your dalvik cache.
7) Once its at the lock screen, done! You can make sure it did its job by using a file explorer with root access (I use Root Browser, if that helps) and go to the root of your phone’s memory, go to system > app, and you should see a bunch of “appnamehere”.odex files.

You will see a noticeable increase in performance with all the system apps like Messaging, Phone, Browser, etc. And because all the base apps are now odexed, you will also see an increase in battery life as well.

List of ROMs confirmed working

• FreeGS3 R6
• Intrigue ROM
• Crimson v4
• Wicked v2

As you can see, this is a fairly simple process, but you’ll still want to make a Nandroid backup, just in case. There isn’t a whole lot of risk here, but you could end up having to start over again with a fresh install, should you mess anything up along the way.

One last thing I should mention –  the initial reboot and odex takes a while, so be patient. Definitely don’t do anything silly, like pull out your battery while the app is working its magic. Have a beer. Before you’re done with it, you’ll be good to go.

The Deodex Me app can be found by visiting Paul’s original thread on MoDaCo. Once you’ve installed, be sure to stop back and let us know how you’re enjoying the new benefits of your favorite custom ROM’s.

Toodles!

Source: XDA-Developers