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B2G OS
  1. MDN
  2. Archive of obsolete content
  3. B2G OS
  4. B2G OS phone guide
  5. Fx0

Fx0

In This Article
  1. Get a device
  2. Updating & upgrading the software
  3. Device specifications
    1. Hardware
  4. See also

The Fx0 is a high-end consumer Firefox OS smart phone, and marks the very first Firefox OS phone release in Japan. It was released by KDDI in December 2014.

Get a device

On release, the Fx0 was available to buy through standard Japanese retail channels. Being a SIM-locked device, it could only be used in Japan.

More recently (late 2015/early 2016), GSM unlocked phones became available, sold by various online shops.

Updating & upgrading the software

The device's system image is locked, so you can only update the software when the network operator releases an OTA update. The device system image is based on Firefox OS 2.0.

Device specifications

You can find more of the device specifications listed on our Phone and device specs page.

Hardware

  • CPU: Qualcomm Snapdragon S4 MSM8926 1.2GHz quad-core
  • Camera: 8 megapixel front, 2.1 megapixel back
  • Battery: 2,370mAh
  • Display: 4.7"/IPS
  • Resolution: 1280 x 720
  • Internal memory: 16GB ROM, 1.5GB RAM   
  • External memory: microSDXC (64GB max.)
  • Size: 70x139x10.5 mm
  • Weight: Approx. 148g

See also

  • Official KDDI Fx0 information portal
  • Official Mozilla blog annoucement

Document Tags and Contributors

Tags: 
  • consumer
  • Firefox OS
  • Fx0
  • KDDI
  • Phone
 Contributors to this page: chrisdavidmills, foxstorm, NicolasWeb
 Last updated by: chrisdavidmills, Feb 27, 2017, 3:02:09 AM
See also
  1. Build and install
    1. Build and install overview
    2. B2G OS build process summary
    3. Build prerequisites
    4. Preparing for your first build
    5. Building B2G OS
    6. B2G installer add-on
    7. Building B2G OS for Flame on Mac OS X
    8. Choosing how to run Gaia or B2G OS
    9. Compatible Devices
    10. Installing B2G OS on a mobile device
    11. Creating and applying B2G OS update packages
    12. Building and installing FOTA community builds
    13. B2G build variables reference sheet
  2. Porting B2G OS
    1. Porting overview
    2. Porting basics
    3. Porting on CyanogenMod
  3. Developing Gaia
    1. Developing Gaia overview
    2. Running the Gaia codebase
    3. Run Gaia on desktop using Mulet
    4. Understanding the Gaia codebase
    5. Making Gaia code changes
    6. Testing Gaia code changes
    7. Submitting a Gaia patch
    8. Gaia build system primer
    9. Different ways to run Gaia
    10. Make options reference
    11. Gaia tools reference
  4. B2G OS APIs