I think you're underestimating the ability of toddlers. At 2-3 years old I could select the paint shop pro disk out of the box (it was a different color), put it into the apple Mac plus. Run the app. Do my digital drawings. Save.
"Leon learned how to use Skype really well. He finds the app in iPhone, opens it, finds the grandma he wants to talk to, opens chat, presses videocall button. And there comes the problem - Leon can't talk yet."
My 4yo daughter can set the foreground and background colors in emacs on her own (the commands are written out in her notebook, but not in any particular order). We were both really proud the first time she pulled it off.
a text editor with bright colors and large fonts is thousands of times better than magnetic letters.
She types by hunt and peck. The was a while where I'd have to help her find the "f" key, etc., but that's pretty rare now. She has a notebook with some words spelled out in it (names mostly: "Cinderella," "Ariel," "Mommy,"...) and she'll type them in and read them, and I'll usually write her some sort of message on the screen when we set it up.
We started doing this last fall IIRC and she'd either play with letters or we'd use commands and type words in together. There was a lot of filling the screen with "*" to make a snowstorm. She's somewhat more independent now but there's still a lot of running back and forth and consultation.