If you want to use the iOS app, or the Windows client you need to connect your player using a pairing code.
1. Log into Spotify Business and click on the name of the zone you want to connect
2. Under "Zone settings", click on "Connect player"
3. Select which player you want to use. If you choose the iOS or Windows player, the pairing code will show up on the screen
4. Enter the pairing code in the Player for Spotify Business player once installed on your iOS device or Windows computer
5. Enjoy the music!