If you install jailbreak tweaks that modify certain apps in particular, then you might find a new free release dubbed LaunchInSafeMode by iOS developer inoahdev useful for troubleshooting when things stop working properly.
This tweak lets you launch individual apps into a “safe mode”-like state in which it launches without the effects of other jailbreak tweaks. In other words, it lets you see if a problem you’re experiencing is caused by a jailbreak tweak or something else.