I'm generally very happy with how my Hue setup works, but for some reason the Hue app sometimes lags on the simpler screens, like the settings tab and configuring the remotes' buttons. The Home tab where you set the scenes / brightness and such usually works fine.
> sometimes lags on the simpler screens, like the settings tab and configuring the remotes' buttons
That's because there is no cloud storage or place to store those settings other than the devices (or the bridge) themselves.
You are not waiting on the app. You are waiting on a request and response to the device over Zigbee to save the settings, which is not an instant action.
Maybe they could just close the screen and finish the work in the background, but I like knowing it completed successfully.