Hi pand0ra :wavey:

I moved your thread to the Sprint All Things Root forum for you.

Unless there's some way to do it I haven't seen, you should never flash a i9500 rom on your phone. The i9500 has different hardware and could brick your phone. Check here for all the roms you can flash on the SPH-L720.

 

You might be able to use some i9500 roms not 100% sure though. I am using the FreeGS4 for the Sprint Samsung Galaxy S4! It is pretty smooth and no issues so far for me. Make sure to do a factory reset and clear the dalvik cache and the cache partition. Did you install a custom recovery like cwm? If not you need that first. Then make a backup of your system. The cache partition is found under advanced in the cwm recovery. Follow the steps that people have on their pages for flashing their roms and you should be fine. Good luck.

 

I wouldn't try the i9500 roms since the phone has different architecture. I think the i9505 and the US carriers can all run each other's roms. Just have to use a kernal made for your phone. I've run i9505 roms with a T-Mobile kernel.

pand0ra, before you try to flash the rom you are doing a full wipe in recovery first?

 

Yep, if you're switching to roms with significantly different framework (TW to AOSP, for example) you need to do a full wipe.

To keep your app info, try an app like Titatium Backup, Datasync+, or ROM toolbox.

If you're just upgrading your ROM version, wiping the Dalvik Cache will do just fine.