As long as we respect the advice of installation, operation is done without too much difficulty. For my part, found no bubble. Just the bottom left corner that did not plastered on the phone screen, but because I had to shift a little film during its installation (the film is the size of the cell phone). But since the time I put it, nothing has changed (the bubble in the lower left corner has not spread and no one else appeared) Tip: just take great care to do so.
