How do ROMs work? What are my options?
I have a AT&T Samsung Galaxy S4 and I am looking for a ROM to replace the carrier version for the following reasons: bloatware, carrier IQ keylogger, and a dislike of TouchWiz. However, I want to keep certain features unique to the S4, which are Airview, Air Gesture, Smart Stay, and Multi Window. How exactly do custom ROMs work? Am I supposed to look for a ROM that has all the features I listed (those are the only ones I need), or can I just get any S4 custom ROM and then somehow install these features through APKs?
What exactly are my options? This is my first Android phone and I really want to get to customize it to my likings.