Problem: Currently having an issue with the Topdon Ultradiag diagnostic scanner, it’s requiring me to update the software to use it but when I got to do the update it gets to the installing phase and then comes up with the message of app not installed and then I am stuck on the 100% page and am unable to use any of the software. Any solution?

Solution:

Make sure your device has at least 5GB of free storage space before trying the update again, as insufficient storage can cause the “App not installed” error during installation.

You can uninstall some of the big software programs like VW and BMW to free up space. After the software update you can reinstall the makers you removed.

Or try doing a factory reset within the android settings then install it after that, before installing any software.
When you have the SD card in, make sure to go into storage settings within the app also to change the standard file path for storage to the memory card.