But unfortunately you are unable to launch Cydia to uninstall the unstable and unsupported app or tweak, but don't worry there is a workaround for that problem. You can manually uninstall the incompatible tweak package in safe mode. Below is the steps to do so.
Manually uninstall Unstable Cydia Tweak or App without opening Cydia.
Go to SBSettings, then click on power on the bottom-right, you are opened up toAnd the SBSettings can be opened on the lockscreen too, therefore you don't have to unlock the iPhone or iPod anyway.
Hope this post helps and see you again in another posts.