Joanne,
My opinion is totally opposite.

I tried it and I think it is absolute garbage. Before coming to BIAB I have tinkered with some composition toys, and still do occasionally, so judging from hands on comparison.
Here is a short video to Yamaha Mobile Sequencer released years ago. I used it to sketch several tunes:

https://youtu.be/IBoSmgLvSPY

Vertical blocks approach looks familiar? Not a $3 app, but for $16 it is gold (for what it is). You can channel it through Audiobus to trigger fancy apps / sounds too. I think this was just a fun experiment for Yamaha aimed at Japanese market.


"BUT you never know where these things end up."
We can argue same about anything. Anything can take a different shape and form, and I will agree with you that "you never know"... however there are things that have more potential than others, of course with exceptions.