Thank you Marty.
I was able to download it to my iPad.
Unfortunately, the iPad is an early version and does not support "Bluetooth LE" (and Apple no longer supports upgrades for this iPad).
So, I use the app on my iPhone or use the universal remote. The iPad would be easier to use than the phone, but I guess I'll wait for 5G iPad.
I can use the app for the caboose cam on the iPad, so I get a nice size screen compared to a phone.