Release free/Foss apk without any payment code and trackers

[Atomsmelody]

Is your feature request related to a problem? Please describe.
This app comes with two trackers of google billing

Describe the solution you'd like
A separate release of free/Foss apk without any purchase code and trackers.

Thanks dev for the first Foss periodic table app.

[JLindemann42]

Hello!

This is something I'm working. Currently some releases (not the latest yet) have apk-version without billing etc. But long-term I'm working on a fork without billing that releases at the same time as regular updates. But I have no date for this and most likely will take quite a while, but I'm working on it!

Thanks,
Jonatan Lindemann