Wes...
I have the latest Pro on an iPhone and Smartlink rev 2.1. I haven't done enough investigation to narrow down the exact circumstances and am really writing to see if this is an issue you are already aware of. While wifi connected with the app swapped out for a long period (say from 5pm to 10 pm), if I tap on the app, I do not see the rotating circle indicating communication with the Smartlink. Any taps on devices to turn them on or off have no effect. Shutting down the app and then firing it back up solves the issue.
Tempe, AZ