The developer relies on the income from Goolge Play Store to keep working on it though:
"I understand that most of my audience here on Mastodon is more ideology aligned with F-Droid but the app sales on Google Play store have contributed significantly to me working (almost) full time on #Conversations_im.
Without the revenue from Google Play I can’t afford this." -- https://gultsch.social/@daniel/111929678072451151