hiya folks
If u could help me with these would be great first off i got an unlocked iphone dont know what version if u could tell me how would be cool right here goes.

1.does the bluetooth do anything cant transfer files to my iphone

2.i got some japanese icons on main screen i want to get rid of

3.if i go to settings then keyboard the writing is in german so is a few of the other settings pages

4.ringtones can we use our own modern music

I dont know that much about computers if someone can tell me how would be great these phones dont seem to be that good at the minute i hope that i can change that.