Closing an iPhone Duo starts a cassette in Deck-Man, and iGeeksBlog builds its app roundup around that kind of idea. Most apps only get bigger on the inner screen; a smaller set from indie developers treats the hinge as a control or the half-open phone as a stand.

Apps where the hinge is the button

  • Deck-Man. Every album becomes a cassette on a shelf; slide one into the deck, close the Duo, and it plays from Apple Music or files on the phone. The clicks and tape hiss were recorded from a real portable player.
  • Toastie. Build a grilled cheese on the open screen, then fold the phone to shut the toaster lid. It cooks out of sight in real time, so opening too early or too late ruins one of its 10 recipes.
  • Fold Accordion. Opening and closing the phone works the bellows, and a learn mode lights the keys to press.
  • Foldfish. Unfolding the phone casts the line, and holding a finger down reels the catch in.
  • Fold & Squish. Paint on one half, close the phone, rub the outside, and open it to a mirror print, the old school paint trick.
  • Fold Focus. A focus timer that builds a small virtual city for as long as the phone stays shut.

The second group needs the Duo half open and standing on a desk, a position the phone holds by itself.

Apps for tabletop and tent mode

  • Tiny Computers. Ten miniature machines inspired by the Macintosh, the Commodore 64, Windows 95, the iMac G3 and others, with the screen upright and a working keyboard below. They type, draw and hide secret files and commands.
  • Delta. The emulator runs Nintendo DS games with the game on the top half and the touchscreen and controls on the bottom, and folding the phone shut puts the game to sleep like the original.
  • MD Vinyl. Half open, the album art stands above a spinning record, and flipping through the collection tilts the albums in 3D as the screen folds.
  • Wakeout. One-minute movement breaks with no equipment, played in front of the camera with the phone propped as a tent.
  • TypeDraw. A notebook that opens when the phone does, with 12 handwriting fonts or one made from your own writing, and a two-page spread when turned sideways.

The big names caught up too: Netflix hands a clip from the outer screen to the inner one, MLB puts the game on the upright half and stats below, and Fantastical lays calendars and tasks out flat. The channel counts those as apps that use the Duo as a bigger screen, a different problem from the iPhone Duo app optimization complaints at launch, which were about apps that didn't fill the inner screen at all. Its top three are Deck-Man, Tiny Computers and Delta.

Of those three, Delta is the one I expect to stay installed. The DS was built around two screens joined by a hinge, so a half-folded Duo runs its games in their original layout. Deck-Man and Toastie are the apps to hand someone who hasn't held a Duo yet.