Question: what apps are bts on?
Answer: Twitter (@ bts_twt and @ BTS_official)
Snow (unknown username)
Vlive (BTS)
Instagram (@ bts.bighitofficial)
YouTube (BANGTANTV / ibighit releases their MV's)
Spotify (BTS / they have their own playlists)
Facebook (I know they use it but I do not. You could probably just search BTS.)