You can also go to Settings>Privacy>Analytics>Analytics Data and see some pretty specific logs on why things crashed or why they were slow. You can see if an ap

You can also go to Settings>Privacy>Analytics>Analytics Data and see some pretty specific logs on why things crashed or why they were slow. You can see if an app used too much CPU time, OOM kills (a.k.a. JetsamEvents, in iOS-lingo), and explanations for app crashes (I can see that iOS killed an app for trying to write to the photos library without permission, for instance).