If your saphe doesn't automatically connect to your iPhone, it's often because the app doesn't run in the background as it should.
Please check the following:
Location is set to Always: Set Location
Power saving is turned on: Turn off power saving
The problem may also be because you shut down the saphe link app completely. Apple has a guide here that shows you how to shut down apps completely on your iPhone: Force an app to close
Forced closing the saphe link app on iPhone, iPad or iPod touch will cause the app to shut down completely and it will no longer run in the background and will not be able to connect automatically to your saphe device.