iPad Mini can't open apps
As 'Dempa' said in comments, you should do a hard-reset:
https://support.apple.com/en-us/HT201559 &lt;- "Force Restart"
If this does not solve the problem, you should back up your info in iTunes (Assuming that you cant open Settings app):
https://support.apple.com/en-us/HT203977 &lt;- "iTunes Backup"
And if restoring doesnt solve the problem, you will have to go into an Apple Service Shop/Center, however they are called in your country, and ask for technical assistance.


**Im pretty sure the HARD RESET step is what you need.

Hope it helps.