As Rob said in his opening post, he hasn't had much time to play with the app yet. I think that is key to getting the most out of any complex bit of kit like ARC Pro. Same with any of the digital race management programs for the Advanced Power Base or any of the other manufacturers systems.
Sometimes from reading these comments, it would be easy to think ARC is a pile of junk. It isn't. ARC Pro is a very neat out-of-the-box digital system with an extremely impressive software package for an entry-level product. It is a complex system and the app needs some investigation and "playing with" before I'd recommend hosting any race events. I'd say that about any new slot car system and think ARC is easier to explore than most.
What I've picked up from the forums is that some users find the smart device platform not to their liking. Everyone is welcome to their preferences. I suspect most new digital users are comfortable with the app, although a user guide would be handy. In the meantime, this forum is pretty good for answering questions and pointing people in the right direction.