Apple said to be working on a 20-inch all-screen MacBook, and I'm cautiously excited

For all the discussion of a folding iPhone, the idea of a folding folding iPad is much more interesting to me. One of my favourite Apple patents from a very long time ago described a single folding touch screen that could be a huge iPad or a pretty respectable laptop: you'd fold it into a laptop shape and type on the glass when you were at your desk, and use it like any other iPad when you were on the sofa, in a meeting or on the train. And it looks like Apple might actually make it.

According to Display Supply Chain Consultants analyst Ross Young (via MacRumors) who's become quite the predictor in recent months, Apple is "exploring all-screen foldable MacBooks", and says that Apple is in discussion with key suppliers about folding notebooks with 20-inch displays.

This isn't particularly outlandish: Asus has already made a pretty impressive folding laptop/tablet hybrid, the Zenbook 17 Fold. But would you want something even bigger and no doubt even more expensive?

Is this a MacBook or a monitor?

Apple's plans are interesting, because according to Young the model would use an on-screen keyboard in laptop mode and an external one when unfolded. That makes it sound like a laptop in both modes, with a small screen when you're on a plane and a big one at your desk. That's no doubt because the predicted 20-inch screen would make it awfully unwieldy as a tablet (though we do love the 14-inch Samsung Galaxy Tab S8 Ultra), not to mention heavy: Asus's folding device has a 17-inch display and weighs slightly more than the current 14-inch MacBook Pro and a good bit more than the iPad Pro 12.9-inch.

I don't doubt that such a device is possible. But I'm not so sure it'd be particularly nice to type on, and I'm certain that it'd be ruinously expensive. And I mean ruinously expensive even by Apple standards: right now folding phones a lot more than their flat siblings; folding laptops are likely to cost considerably more, which perhaps explains why Asus is keeping quiet about its folder's price until May.

But maybe I'm thinking about this wrong. Maybe the goal here isn't to replace the MacBook Pro or the iPad but to come up with some whole new category, something that isn't a big phone or a folding tablet or a laptop at all. 

Maybe Apple doesn't know what it's for either: after all, it launched both the original iPad and the Apple Watch without any clear idea of what each device was for. The original iPhone didn't have an App Store or a camera, and today it's defined by both. So maybe this is a tabula rasa, a blank (folding) slate for us to work out what to do with it. There's certainly plenty of time to think about it: if Apple makes it, we're unlikely to see it until 2026 or 2027.

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