So, for example, if you subdivide 4/4 into 16th notes, then the metronome would say:
1e+a 2e+a 3e+a 4e+a
One thing where this has been especially helpful for me is that I added support for asymmetric rhythm patterns. In pop music, it's common for songs to use a 3-3-2 rhythm pattern with eighth notes. Even though this is usually written out in 4/4, in my app, if you set the rhythm to 8/8 and explicitly define the beat groups as 3+3+2, it will count this for you! This ends up being:
1+a 2+a 3+
You can see an example of what that looks like here! https://labs.tiffzhang.com/count/?bpm=100&ts=8-8&sub=2&vm=co...
What do other people think? I'd love to hear if this helps anyone else with their music practice or if people have thoughts on things they'd like to see from this!