Firefox OS will look familiar to smartphone users. Here's the app screen shown on a ZTE Open.
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Cut the Rope on Firefox OS
Cut the Rope, a classic mobile app that's made its way to many different operating systems, works on Firefox OS. It's shown here on a Geeksphone Peak developer phone.
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Gallery app on Firefox OS
The gallery app on Firefox OS presents photos as an array of thumbnails that scrolls vertically. To do something with a photo, like share it or edit it, you must tap on it to open it.
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Photo editing on Firefox OS
Firefox OS's gallery app lets you crop photos, apply some basic color filters, adjust contrast, and share photos with a system resembling Android's "intents." That lets you pick a variety of destinations registered to handle photos.
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Firefox OS dialer.
Firefox OS's phone app includes tabs for a dialing keypad, an address book to find contacts, and a recent call list. This is on the Geeksphone Keon, a lower-end developer-oriented phone.
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Firefox OS clock.
Firefox OS includes a clock app, unsurprisingly, which you can use to set alarms. The Geeksphone Peak shown here has a fairly sharp 4.3-inch QHD screen.
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Firefox OS camera app
Firefox OS's camera app in action on the Geeksphone Peak. The phone has an 8MP back-facing camera and a 2MP front-facing camera.
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Firefox on Firefox OS
Powered by Firefox OS, the ZTE Open naturally includes the Mozilla browser, too.
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Firefox OS lock screen
The ZTE Open with first stage of the two-stage Firefox OS unlock screen. Pulling up from the bottom of the screen then reveals an option to unlock the phone or to launch the camera.
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Facebook integration on Firefox OS.
Firefox OS's contacts app lets you import contacts from Facebook. Mozilla plans to add support for Web-based mail systems such as Yahoo Mail, Gmail, and Hotmail later.
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A long press on the home button invokes the task switcher. This view shows one rough edge on the experience: the horizontally oriented Cut the Rope app doesn't fit well in the vertically oriented thumbnail.
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Firefox OS on a Geeksphone Keon
The opening screen of Firefox OS running on a Geeksphone Keon.
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Geeksphone Peak running Firefox OS
The Geeksphone Peak, designed for developers, is one of the first phones to sport Firefox OS. It's got a dual-core Snapdragon S4 processor running at 1.2GHz.
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Firefox OS gallery app on ZTE Open
Firefox OS, shown here on the ZTE Open, has a gallery app, but if you want to share photos, you have to do so one at a time by opening it first.
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Dialer app on ZTE Open
The ZTE Open feature a traditional phone dialer, with tabs along the bottom to access recent calls, contacts, and the dialpad.