So I only l play mobile (noob alert). I have been playing since before hard mode was released for it. When 1.2.4 came out(the first, extremely unstable version), my character got to join one world one time, then it would repeatedly crash when I tried to join any worlds, then when I went to the character selection menu, then finally whenever I would start the game. I went to the customer service guys with an email explaining the problem. They told me to delete my game and redownload it.
Big mistake
It kept happening after a few days of a brand new play through. But the day after CS told me to delete my game, they said, on these very forums, "to everyone whom we have told to reinstall terraria, DONT. The entire issue is due to file corruption. We will fix the issue soon.
FfffffffffffffffffAAAAnyways, leave a like if you had this problem, way back in that era of mobile.