1: Phone calls (Alot work related)
2: Google/General web browsing
4: Social media, which is also mostly work related as I personally dont use facebook etc. I do use instagram however.
Then all my other phones I usually mod them absolutely to my preference, and many of them I overclock just to see how far I can push them on a safe level.
I have a couple of phones built into my walls in the kitchen, living room and bedroom etc. From basic stuff like showing the clock (bedroom ceiling), to more advanced stuff as being my kitchen media centre!