I’ve tried a few free apps to track my Facebook friends, just because I guess I have abandonment issues and want to know if someone unfriends me? Anyway, this is the only one I’ve found that works correctly. I haven’t tried the new Instant mode, but the regular one works for me. When my numbers change, I can login and see whether someone has deactivated/reactivated, added, or unfriended me. I can’t speak to the “most active followers” feature because I don’t check it, but it’s oddly comforting to know I’m not losing friends, they’re mostly just deactivating their accounts. I’m freely appreciative of this app!