You can create local m3u file (or download straight from your provider) and open in VLC.
As someone mentioned. GSE works great in Iphone.
playlist files work in VLC (.m3u8) if you have those available for your provider.
I've never been able to get xstreams to work in VLC.
Use lillyplayer
IPTV Smarters or GSE IPTV works great on iPhone