To use it in the U.K., there are two options.
You can subscribe as a uk subscriber. You get audio commentary, replays - including extended highlights and full match replays, plus news features and interviews. Think it costs about 30-40 quid and yes you need WiFi and data.
The other option is to subscribe as an international user, but you’ll need a VPN which makes ifollow think you’r abroad - for this you get the above plus live streams of the matches - but see problems above. It worked for me for Accrington and i dipped in to the Burton game for a bit as wasn’t there. Was at the match tonight so cant comment on that. Think it costs about 120 quid.