"Charles F says: June 20, 2013 at 5:22 pm the last post is correct, the ios 7 beta feels very broken right now, however to answer your question you will not lose anything except for apps and music(only the data and settings of the apps will be kept), you will have to resync the music and apps since you must restore as new iphone in the process(not unless you directly update to ios 7 if you are a de" . . . .