I've seen a lot made about the accusation about these apps being a "taximeter", but what is the license constraint on how a private hire vehicle actually charges for a journey.
Is it a fixed price agreed in advance? (guess not)
Is it based on time?
Is it based on an old fashioned ruler measuring a distance on a map?
Are there fixed fees between waypoints that gets added up?
Is it just the driver suggesting a figure off the top of his head (feels like it sometimes).
That is the crux of the problem. While the licence may say that "private hire cars cannot use taximeters", what does it say should be used instead? And an app on a phone is not a taximeter. A taximeter is a well defined calibrated physical entity that is hard connected to the vehicle, and that is covered by law.