Try thinking about some minor annoyance in your life and if you can solve that with a simple app, or something you really enjoyed that could be made into an app.

Some things I’ve done —

StreamSwitcher for turning Apple Music links to Spotify links —https://apps.apple.com/us/app/streamswitcher/id6450388510

Cancel your gym membership online — https://byebyefitness.com

Step by step translations of the Dao De Jing with beautiful artwork — https://apps.apple.com/us/app/daily-dao/id6465685578