Can't open app

I updated my iOS last night and now Scrivener won’t open at all. The logo flashes for a moment then it goes back to the home screen. Any ideas?

If you use Dropbox to store and sync your project:
Double tap the home button and force-quit Scrivener from the list of recent apps by flicking it up.
Go to Settings app > Scrivener > Reset Scrivener > tick Clear Dropbox Sync Cache and close Settings
Start Scrivener and see if it helped.