The Stream Deck Mobile app can load the same profiles - but you have to set it up to do so.
I tested it briefly on an iPad this morning. It took two attempts to get it to sign onto the network.
If you don’t maximise it (i.e. fill the screen) the buttons are about 20% larger in size on an iPad than than the buttons on a Stream Deck. In this resolution the icons look sharp and, to my mind, better and more informative than when they’re on the Stream Deck - that’s purely down to size. If you do maximise it, the display stretches to top, bottom and left edges but not completely to the right edge; some space is reserved for a setup button. It looks a bit weird not being centralised and the icons lose resolution when they’re stretched out to this size. It occurs to me that the new XL Stream Deck would look pretty good on an ipad in unamximised resolution although there would be a fair bit of space top and bottom. I can’t see an XL layout working on an iPhone.
I loaded two profiles: my own default setup and Notation Express. Everything seemed to work OK, I didn’t have any issues with responsiveness. I tested it briefly with Dorico and everything I tested happened as expected.
I did have a problem with automatic switching between profiles. On OSX, Stream Deck automatically changes profiles as you switch programs. So, for example, if I switch to Dorico, Notation Express loads automatically on my Stream Deck. The first thing I noticed was that that didn’t happen on the iPad. I had to manually change profiles - not good. But worse was to come. When I went back to OSX, the setup there had changed too and I now had to manually change profiles there as well. I don’t think I did anything I shouldn’t have done during the setup process so I can only assume this is either a bug or something that’s yet to be addressed in the software now that iPads and iPhones are linked.
I really only did this to test it. I’ve since uninstalled it and after a bit of faffing about have my Stream Deck back to working the way it was.
Final thought: although I’m not a fan of subscription services, I don’t think the charge is bad value (certainly not when one considers the cost of the unit) and if they sort out the profile switching issue it’s a very reasonable alternative. You lose the touch and feel aspect of the buttons but, to my mind, the display is better. That said, I’m sticking with my Stream Deck.