@lk108
I don’t have Ubuntu Touch, but would like to look into the source code, especially since it is written in QML. I made a Kirigami2 client ~link2xt/kdeltachat - sourcehut git, it is functional and I use it sometimes, but it is not actively developed at the moment. Maybe at least some C++ parts can be shared or we can make a single convergent QML app for all kinds of mobile Linux. There is a related thread at Native Client for Linux based mobile OS - #19 by link2xt
Wrt. licensing if you intend to publish as GPLv3, see how it is done in ~link2xt/kdeltachat - sourcehut git. I think it’s a good idea to have an explicit OpenSSL exception because its compatibility to GPLv3 is sometimes questioned and boils down to whether you can consider OpenSSL a “System Library”. The “GPL-3+ with OpenSSL exception” is also what Kaidan application does in LICENSE · master · Network / Kaidan · GitLab