We were able to reproduce this issue on our end and have forwarded it to our Android developer for inspection. we’ll keep you updated on the progress and let you know once a fix is available. In the meantime, please disable the SonarPen in the spacedesk Android Viewer settings under Input Devices -> Pen -> SonarPen Stylus when not in use.
We have released a new spacedesk Android viewer in the Play Store. This release contains various bug fixes, including the app crash when Sonarpen is enabled during USB connection. Please try it on your side and let us know if this fixes the issue for you.