Facebook adapter

is it required use of Facebook adapter for each placement means on every page or use on 1st page/home page. when setup mediation. please answer fast.

Just drag on screen 1 that’s it

Only one time not compulsory for every screen

I also have a question about facebook adapter that should we use both facebook ads and admob ads components to setup mediation or can use admob only.
Plzz help…

Please Help me… Waiting to update my app.