You can report crashed games to Customer Support by submitting a support ticket along with the match ID of the aborted game.
To find the match IDs for aborted games, open the Skillz app and select the HOME screen. Scroll down to the COMPLETED section and select the matches that were submitted as ABORTED. Tap each match information banner to access the details of the match, and the match ID will be located at the bottom of the results screen.
Additionally, if they detect that a game had an issue, you may see a REPORT A PROBLEM button after seeing the results of your match. Tapping that button will walk you through the process of reporting the issue to them: