said by ExoticFish:I'm not surprised they're iPhone users use the most data.
Do you realize you just said "They are iPhone users use the most data"?
Their is a possessive, i.e., "Their property", or "Their customers"
There refers to a place, i.e., "I was over there yesterday." or "I am looking at flowers over there."
They're is a contraction for "They are", i.e., "They're cute."