Dragon Project: Ryuuin no Senritsu Vol.1

[cal]

Rei Kondoh says he contributed some music for this game on his website: http://www.reikondoh.com/Information/info1.html#drapro

2016.06.24
Android™ / iOS「ドラゴンプロジェクト」一部音楽を担当

好評配信中のAndroid™ / iOS アクションRPG「ドラゴンプロジェクト」の
音楽の一部を担当しました。

I couldn't find any info about the other composer(s).

[Teioh]

Tadayoshi Makino was also involved in the music:
https://www.spinsolfa.com/works

ドラゴンプロジェクト
October 02, 2016
開発：COLOPL
対応機種：iOS / Android
​一部楽曲制作を担当させて頂きました。

[cal]

Thanks. I also found it on Unique Note's website: http://www.unique-note.co.jp/works.html

Tetsuya Shibata and Yoshino Aoki both posted on Facebook that they were in charge of the main theme and other tracks.

[CHz]

Keiki Kobayashi too lmao: https://www.keikikobayashi.com/works