Use an iPhone/iPad to display the data - and another iOS device as a sensor/protractor.

This has the advantage that you can read the display device more easily - or take it with you, when you place the wedges underneath.

Note: This function needs to be unlocked via an in-app-purchase 'Support for Sensor App'.

Here is a short video showing how it all works:

Install and launch the free 'Level Assist Sensor' app on the other device.

https://apple.co/3RwF6Jz

Scan the following QR code with the camera app on the other device - this will take you directly to the app store to download the app.