Unpivoting table might be a great way to create filters in PowerApps.
Store you r
Unpivot it using this code:
SELECT [User],[App],[Permission] FROM (SELECT [User], [App1], [App2], [App3] FROM [UserApp]) p UNPIVOT (Permission FOR App IN (App1, App2, App3) )AS unpvt WHERE [Permission] = 'Yes' ;
Store that code to a view to easily retrieve it from your PowerApps.