X's rEvo Checklist
Here is a screenshot (phone version) of the first screen (out of a total of 4) you have to walk through in order to complete the build. The whole series of screens can be seen on Google Play Store.
As a rEvo rebreather diver, I have found convenient to have an electronic version of the build checklist. It prevents inadvertently skipping a step during the build, with potentially disastrous consequences. I haven't considered doing the same for the pre-dive checklist for the simple reason that using a smartphone in this situation is not convenient.
I designed this Android app as a fun project while trying to learn how to use App Inventor (I now migrated the app to Thunkable). It doesn't have any bell-and-whistle found on your average time-wasting app, but should do the job. Plus it is free (and ad-free).
You can download it from the Google Play Store (X's rEvo Checklist) by clicking on the icon below:
I originally used the app on a 7" tablet. I now use it on a basic smartphone and a 10" tablet. It works just as fine on all these platforms.
I have set up a Google User Group for questions, suggestions or bug reports on the app.
Disclaimer: Android, Google Play and the Google Play logo are trademarks of Google Inc.