Same problem here with Android P on a Pixel 2 XL. Have just tried AirDroid_4.1.8.1.apk you suggest and same problem - It crashes after displaying the Airdroid4 start screen.Kindly uninstall AirDroid on your phone first, then download and install the package as below to see if it works.
https://dl.airdroid.com/20180521183633_AirDroid_4.1.9.2.apk