Yes and no. mzanetti and I aren't actively looking into still supporting those (as mzanetti uses Ubuntu Touch, and I use Sailfish). But someone else has recently fixed some (build) issues in the app for the N900. And he also said he wants to fix the N9 app. But it will probably take some time until those versions are back on par with the Ubuntu and Sailfish version. Although some things will work automatically as they're platform independent (like support for browsing addons, and the upcoming version will support browsing playlists, those things should work on all platform without requiring modifications in the platform specific code).