But, you should know after the tool jailbreak released usually still many apps or tweaks certain not yet support the IOS version you are running on the device, because the developers who make tweaks and applications, requiring several days to update their products in Cydia to be reused in the latest iOS.
To avoid you from these problems, you should consider whether tweaks or the application you want to install has been supported by iOS on your device or not, you can read through the information contained there. If not, you should be patient.
Usually repo or official source and a default will not allow to install apps or tweaks that are not compatible with your iOS. But it is different if you install from source or repo third party who is not authorized, you can install apps or tweaks that are not yet compatible with the risk can cause the device or app cydia crashes or enter into save mode and the worst is stuck in boot Apple logo.
To fix the error or crash after install cydia incompatible tweaks or apps, there are several methods, but be better before restore and jailbreak again you can try this way.
Step 1: If your device jailbreaknya not stable because it usually has just been released, such as iOS 9, you should not do force reboot, but turn off in the usual way, by pressing the power button a few seconds to appear "Slide to Power Off", then turn off as usual.
Step 2: Once your device is fully Off, turn it back on your device by pressing the power button, along with pressing the Volume UP.
Step 3: Once the Apple logo appears, release the power button, but do not release the Volume UP button until your device turns back on with normal condition.
Step 4: Then please check tweaks or application, before you cydia error or crash, then uninstall it.