[alimbada]

I may be wrong but I don't think your app needs to be open source to publish it on F-Droid.

Edit: Sorry, seems I was wrong [1] but you can host your own F-Droid repository which can be added to F-Droid by users to install your app from.

https://forum.f-droid.org/t/non-open-source-apps-are-allowed...