Hmm, I don't think it's necessarily Apple-only.
It says "本アプリは、スマートフォンより
Apple storeなどからダウンロード可能です" Which means: "This app can be downloaded on smartphone from Apple Store
etc."
In other words, Apple Store
and other places.
--
Anyhow. I think it's a nice idea. Although the cynical part of me also thinks her team will forget about it after a month or so
Thanks for posting, Aderianu~