Security App for 7C

Hi,
I have an 7C home tablet and there is no standard screen lock.
I have tried several application locks but they are for mobiles and not specifically for a tablet.
The locks to work but there is a home button on the tablet screen and this unlocks it without having to enter a code.
The only other option is to put a lock on each app but i would prefer just one lock instead of locking each app individualy.

Does anyone have any ideas or tips?

Cheers,
T