I was trying to mold Todoist into doing what I need, and these "workarounds" for implementing a "start date" seem insane to me vs just adding a start date field...: https://todoist.com/help/articles/does-todoist-support-start-dates
They say it's because they don't want to hide tasks, but even just a start date field that doesn't hide the task would be a huge improvement since you could still filter and sort by it!
They have two weeks trial. I will check that out.
Anyways, thanks, nice suggestion. There is also https://morgen.so/. I suppose that it should work in a similar way.
p.s., It is developed in Switzerland (same as AM), because I got an impression that that is important point on this subreddit. :D
Have you considered just making a separate super lightweight quick entry app available?
That is, something like add quick event https://play.google.com/store/apps/details?id=com.a3w4u.addquickeventfree