I had a required field, a single character which was a manual entry of Y or N. I changed it to an integer checkbox.
Everything generated just fine.
The app loaded fine.
When I went to save the record, with the checkbox checked (the default), everything was fine.
When I then saved with the checkbox unchecked, I was prompted that the checkbox field (not checked) was required.
I think one of two options is appropriate. Either:
1. In the designer, if checkbox is selected it should remove the required attribute.
or:
2. If the required attributed is set for a checkbox field, then it (required) should be ignored in the generated app.