You can buy one now. Not open source hardware, and there's probably closed binaries in there somewhere, but you can buy a BQ Aquaris M10 with Ubuntu Touch insta

You can buy one now. Not open source hardware, and there's probably closed binaries in there somewhere, but you can buy a BQ Aquaris M10 with Ubuntu Touch installed. The thing itself has a command line and in theory you can compile your own programs and install packages with apt, though you are heavily discouraged from doing so. (the software is not very good yet, and it's not really usable, but I'm biding my time)