Running Android apps on postmarketOS with Anbox, by running parts of Android next to the Linux userland. Of course not the recommended way to run apps on postmarketOS, because it requires much more resources and doesn't free us from the Android eco system. Nevertheless, it could be helpful with migrating from Android and it is surely an interesting technical problem.

Update: using labels now for this, instead of a milestone: https://gitlab.com/postmarketOS/pmaports/-/issues?scope=all&utf8=%E2%9C%93&state=all&label_name[]=Anbox