We’re curious what you think!
Personally, I see one use case for myself: connecting a phone like this to an external monitor, keyboard, and mouse. And that’s not some far-fetched or extremely rare scenario — that’s exactly how I would use it when traveling far from home.
And since I normally use Shapr3D on a computer, this setup would give me a very similar experience.
At the same time, I’d still maintain a high level of mobility. These days, almost any hotel has a large TV that you can connect to, while a small keyboard and mouse fit easily into a backpack and barely take up any space. And to be completely serious, I even have a portable 15-inch monitor that I usually take with me when I travel.
I guess it could work okay if the iPhone Duo has decent enough support for the Apple Pencil. One main issue I could see on that front is the fold in the middle of the screen. Like any other folding phone before, this one has a noticeable middle crease in the screen as well. Not sure how annoying that would be with the pencil.
The other thing of course is cost. For the price of the Duo you can get yourself a top of the line ipad pro, which certainly is more usable for shapr on size alone. But if you absolutely have to have CAD in your pocket, why not.
For now I am on a Mini5 AFK (my projects often have to be slimmed, but still useful) expect to be replaced as soon as Mini7 is released.
Playfield since yesterday:
iPhone Duo 512GB $2,199.00
Mini6 512GB $1,049.00
(And then I have none, nor do I want any mobile phone.)
I would definitely consider the Duo, IF the screen with pen works (as good as expected?) AND Shapr is ‘ported.’
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I am using shapr3d on Mac and was considering getting an iPad with pencil only for CAD when I’m out of office.
When I saw that iPhone duo supports the pencil my first thought was: If shapr3d works on this thing I will immediately buy it. Because why should I carry an iPad and a Phone if I could do sketches etc just on the duo?
I would see it more as a “get a quick sketch of an idea” kind of device, I guess I would still finalise the project on my Mac. But the just in time sketching is what I really miss. And people always have their phones in their pockets. So it’s a big PLEASE make it work from my side.
I’ve been using Shapr3D on an iPad mini 5 ever since it was introduced, together with a laptop or Mac. The main reason I use the iPad mini is that it’s perfect for quickly capturing ideas while sitting on the couch, traveling, or whenever I’m away from my desk.
However, there are many situations when I don’t even have my iPad with me. That’s why the idea of having Shapr3D available on the Duo is really appealing for the way I use the app.
On top of that, the Duo is relatively affordable. It costs only a little more than my combination of an iPhone Air and iPad mini. If Shapr3D becomes fully usable on the Duo, I’d definitely go for it.
I’m hoping the developers will add support for the Duo. If not, maybe Apple will convince them to do it! 
Let us know about whether you will support it before the preorder please 
I think it would be great if you support it.
I second this!
I model almost exclusively on Shapr3D on my iPad for personal and side business projects. Shapr3D support on the iPhone duo was my very first thought when I started seeing rumors Apple would be announcing a foldable!
I would love to be able to ditch a device and use solely my new iPhone duo to create. I’m begging the developers: please support the iPhone duo! This is essentially the make or break app for me to purchase this awesome new device.
Not sure why you would even ask. Isn’t it basically the iPad app codebase? Is there a lot of complexity to support the Duo?