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.