Check out my install guide on Galaxy Note 3 softModder for step-by-step instructions, just make sure to substitute the OneClick file for the one specific to the GS4. Make sure to check out my warnings before proceeding, as this build could brick your phone.
The builds will largely have the same characteristics, such as:
- The Good: Smoother user experience, better battery life, and camera improvements.
- The Bad: Inability to revert back to Jelly Bean, lack of achieving root, no ART implementation, no third-party case support (for now), the possibility of losing data connection, and some apps no longer working.
But there are some specifics to note for the GS4:
- Reports of users not being able to move or save images.
- App crashes and reboots when trying to play videos.
- One user was able to successfully roll back to Android 4.3, but one case does not mean it's easily, or readily, achievable.
Remember, test builds are just that, made for testing. In all likelihood, we're still a few builds away from a stable release, but if you just can't wait, give this update a shot and let us know your opinions in the comments below.