Welcome to the community! Titanium backup pro is a must if you're going to be romming and modding you're android devices. Custom roms are definitely the way to go especially being new to android modding. There are a few really smart dudes developing great custom roms for the n9005a. They do all the work that you would want done and they're really good at it. I recommend knoxraid by @drakeymcmb
. He has been involved with romming this phone since before we had a recovery to flash from. There a bunch of helpful people that follow his thread.
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