Assuming you’re playing on PC, you can use a screen mirroring application like Spacedesk and pop the EFB out (right alt + click) and have it on your tablet. Certainly a native app that connected to the sim would be a lot nicer though.
In my perfect world we would have a native app running on Android or IOS which would display the EFB and the various avionics screens (based on whatever plane you’re currently flying) exactly as they’re rendered in the game, with touch support that wouldn’t take focus away from your main screen. You can sort of do this now with either screen mirroring or an external monitor but it’s a fairly clunky experience and I wish it was smoother.