Part of the problem of "getting the mobile ports ready" is the fact that some of the issues are connected or at least related with other, major changes.
For example, the mobile versions are lacking shader support. Adding these requires switching away from the fixed rendering pipeline, which is also planned for the desktop versions as well, so it would be twice the work implementing this now for mobile only, rather than waiting for desktop as well.
Another thing I'm actively trying to find some nice solution is access to the native activity handle. Since SFML doesn't have anything similar so far, this requires adding something new, which at the same time could be extended cross-platform (e.g. process handle on desktop versions), so this is also a bit more than just adding a new static function somewhere.