There was an update that was just released today.
On the Mac side, go to Astropad's top bar menu and select "Check for updates"
To update the iPad app,
Open the App Store on your iPad.
Tap Updates, and it will show if an update is available.
If you still receive error messages after updating both apps:
- Try restarting both Mac and iPad.
- If the restart did not change anything, deleting both Mac and iPad app, and reinstalling them onto your devices.
The Mac companion app is always available here: http://astropad.com/downloads/
Let us know if the issue persists.