Echo needs to be in the foreground of your phone to establish a connection. Once connected, it can run in the background. 

How to connect

1. Open Echo on your phone (you do not need to do anything on your watch). Tap to start so it says, 'Waiting to connect'
   
2. On your Echelon screen, select your workout
   
3. Find and tap the heart icon. Echo will auto-connect and start displaying your heart rate onto your screen (can take 20-40 seconds)
   

Additional info can be found on Echelon's support page.