I coupled the Deeper with an iPhone 4s OS 7.1! After initial problems I have come to the following procedure which maintains the connection constant:
Deeper put into the water - without water no Funkton)
iPhone Settings> Bluetooth> click Deeper and wait> it appears after 3-5 sec. to indicate you confirmed with OK> now the previously installed app will automatically open and the connection is established and maintains.
The app then displays on the right side of the water temperature and depth on. If fish show up in the transmission zone are displayed as symbols with depth display.