People like different apps for many different reasons. Depending on the type of internet service, phone or other devices you have apps will work differently.
These apps are pre-loaded with the servers URL. When you go to the app download links you will click on any of the APKs to download then enter your username and password
Server 1 Atomic app download link https://unitedstatesiptv.com/server1apps
Server 3 Ultima app download link https://unitedstatesiptv.com/server3apps/
Server 4 Platinum app download link https://unitedstatesiptv.com/server-4-apps/
Make sure to clear your cashe on your devices 3 times per week and restart your router 2 times per week.
Restarting your firestick everyday will increase quality. Well worth the 2 minutes it takes.
We also recommend installing an external player on your Android devices such as VLC and MX player for a better viewing experience due to different stream formats VLC http://www.videolanorg/vlc/index.html
MX Player http://appurse.com
For IPhone https://apps.apple.com/us/app/247-iptv-player/id1419998058