Why would anyone want a foldable phone? That's easy: You want a pocketable phone that still has a display large enough to truly enjoy books, magazines, games, and perhaps do some work without squinting.
With the iPhone Duo (read our review here), Apple did an amazing job with the user interface, as well as optimizing its own apps to look great on the Duo. But it's up to third-party developers to bring their apps up to speed and create versions that play nice with the Duo's dual displays and all that screen estate on the inner display.
The news here is mixed: Many apps, even some very popular ones (we're looking at you, Google), still haven't been redesigned to look great on the Duo. But among those that have, there are a couple that really stand out in terms of design and creativity. Here's our list of the best iPhone Duo apps so far.
Two notes: I've skipped Apple's own apps. They look universally great, but it's to be expected, and everyone who gets the Duo gets all of them anyway. Second, some of my experience comes from beta versions of these apps that were shared with me in advance for the purpose of testing; your experience on finalized apps might be slightly different (hopefully even better).
Netflix
One of the first apps to receive a complete Duo overhaul, Netflix is the one you'll show to friends on your new foldable iPhone. Not only does the larger inner display show a ton of content, but the app does different tricks depending on how you fold and position your iPhone Duo. Not all of it will be useful, but ultimately, video streaming apps are perfect companions for the Duo, and we're glad to see Netflix looking ahead here.
Edits
Instagram's video editing app was one of the first to get thoroughly optimized for the Duo, and it's the type of app that really takes advantage of the extra screen space. Video editing can quickly get complex, and handling a video project's minutiae on a tiny phone display simply isn't as good as doing it on the Duo's large inner screen.
As a side note, Instagram, too, has been revamped for the Duo, but given its native vertical bias, it looks a bit odd when you hold the Duo horizontally. It's not bad, but I think Instagram's designers will probably do some more tinkering to really make use of the extra screen real estate on the Duo.
RainViewer
Weather app makers took the Duo seriously. I've gotten numerous pitches from several app makers that have updated their apps to play nice with the Duo. The one that looked nicest to my eyes was RainViewer, whose updated iOS app is currently under review by Apple. The app offers an incredibly clean, beautiful weather map focusing on incoming precipitation.
Other weather apps that have updated their apps for the Duo include Carrot Weather and Mercury Weather.
Deck-man
The Deck-man mimics a walkman on the Duo. Yes, an actual, analog walkman, with cassette tapes that you virtually drag from a catalog on the left to the player on the right. The visual trick that Deck-man does is that the playback doesn't start until you've folded the iPhone Duo, as if you were closing an actual Walkman. This is way too annoying to actually use as a serious music player, but it's a nice novelty idea that you just cannot have on a normal, candybar phone. Your friends that were born in the 80s or earlier will probably be delighted with this one. Anyone younger will probably give you a puzzled stare.
Headspace
This meditation app is an example of how you can create a very effective, Duo-friendly app with simple graphics and smart design choices. When I opened the app on the Duo for the first time, the smiling sun logo rising across the Duo's entire display brought a smile to my face.
Finalist
Finalist is a beautiful daily planner/journal combo which has been thoroughly optimized for the Duo and looks absolutely beautiful in all orientations. This is where the fact that the Duo's inner display is matte really shines; spread out the phone on your desk with Finalist on, and it'll look like a wonderfully themed notebook holding all your tasks and meetings.
MD Vinyl
Sorry to include two retro music apps, but both Deck-man and MD Vinyl are perfect for showcasing what the Duo can do. Instead of cassette tapes, in MD Vinyl your music turns into records. To start playback, you need to actually move the needle onto the record, which will bring a true vinyl fan to tears (and make them subscribe to this app, which, frankly, is far from necessary to enjoy music). Yeah, it all works and looks nice on the regular iPhone, but the Duo's large display was made for apps like this, and the experience is just so much better there.
Bonus: Any app in side-by-side mode
The iPhone Duo has a special side-by-side mode which allows you to have two apps opened next to each other in landscape mode, and it immediately makes even the most pedestrian apps so much better. On a video call with someone and need to check out the weather? Pull up the Weather app next to your video call, and you'll feel like a multitasking machine, handing out weather reports like a pro. Numerous apps like email and calendar work so well together that you can even opt to glue them together persistently.
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