My iPhone wont boot up. It's stuck on the silver Apple logo. It happened when I changed my theme in Summerboard. After I selected my theme, the soft reset hanged (littlte circle kept spinning). So I manually reset and all I get is the Apple logo. I've tried holding the home and sleep button together to restart and let go of those buttons when I see the Apple logo, but this is not working. Any ideas causing the issue? I hope I don't have to restore.