They can build a keyboard into it, sure. It’s just UI elements and a bunch of buttons. Won’t be a good keyboard, but it can be done.

The GPL explicitly allows selling the software, like a proprietary software product. You don’t even need to have the code up in a public repo. What you DO need to do, though, is provide a reasonable way for customers to get the source code, and send it to them if they ask. Just because a project is GPL doesn’t mean you’re entitled to the source for free. Of course, if someone buys it and requests the source, they can do whatever they want with it, including uploading it somewhere. Which in the end, essentially makes it available to everyone. Which is the whole point!

All of this only works if the owners of the code respect the license. In this particular case, I don’t believe a contributor agreement was ever created, so if the new owners want to close source the apps, they’ll have to get permission from all contributors, or drastically rewrite those contributions.

But again, this only matters if they respect the license in the first place…

Unfortunately, it doesn’t look like that BBC experiment is going well. They’ve barely posted anything, relative to what they could post. They should set up their systems to auto-post to Mastodon when they post to Twitter or where ever else.

Probably ultimately wasn’t their decision to make.