It's a waste of time really isn't it?
I've not had my drone in the air much, but today in the park, nobody around, it just keeps loosing signal.  I walking right underneath it and it is not really that high.
Signal was in and out, but it eventually just dropped off completely.
In fairness when it did, the return to home was pretty cool.

But I really need to get a proper controller.

OK to take off, snap one or two shots then land but not the best solution for flight.

Flying with a phone as a remote is definitely not comparable to using the remote. A lot more distance, better flight control, better signal. You even feel more secure flying the spark.