I use iOS, Android, and Mac OS. I have found one drive to work very well. I haven't encountered any issues with syncing. I used to use copy as recommended by someone above me, but I have found issues with the iOS version of the app. For example, when viewing pictures inside of the copy app I couldn't zoom in in the corners without it automatically moving me to the center of the picture. Also I didn't like when they redid the iOS 7 app they didn't use the native sharing within iOS 7. Although I do miss copy, because it's synced well with my Linux computer