I have a Spark with the controller.. I upgraded my smartphone to a  Samsung A52 unlocked.  Everything worked fine with DJI go 4 until the last software update on the phone. Something changed with Samsung which caused the DJI go 4 application to stop working.  I am so unbelievably upset because there's nothing else that you an use for the Spark to upgrade the software for the drone.  It has been a nightmare trying to get through to to Samsung and DJI. I am going to try a "refresh" which takes the phone back to its original version.  Wish me  luck...
Paul Reilly

I have a Spark with the controller.. I upgraded my smartphone to a  Samsung A52 unlocked.  Everything worked fine with DJI go 4 until the last software update on the phone. Something changed with Samsung which caused the DJI go 4 application to stop working.  I am so unbelievably upset because there's nothing else that you an use for the Spark to upgrade the software for the drone.  It has been a nightmare trying to get through to to Samsung and DJI. I am going to try a "refresh" which takes the phone back to its original version.  Wish me  luck...
Paul Reilly