Firefox is compatible with Android 2.2 and above devices. Installation requires about 24 MB internal storage, 384 MB of RAM and a display that is at least 320 pixels high and 240 pixels wide. You can download Firefox for Android or search for Firefox in the Google Play store. list of suppoted mobiles Phones

Acer

   Acer Liquid mini E310 

Alcatel

   Alcatel One Touch 903
   Alcatel One Touch 908
   Alcatel One Touch 918
   Alcatel One Touch 979
   Alcatel One Touch 990 

Garmin-Asus

   Garmin-Asus Nuvifone A10 

HTC

   HTC Amaze, 4G
   HTC Aria
   HTC ChaCha A810e
   HTC Desire HD (AT&T Inspire 4G)
   HTC Desire S
   HTC Desire Z (T-Mobile G2)
   HTC Doubleshot (T-Mobile myTouch 4G)
   HTC Droid DNA
   HTC Droid Incredible
   HTC Droid Incredible 2
   HTC EVO 3D
   HTC EVO 4G LTE
   HTC EVO 4G, EVO Shift 4G
   HTC EVO Design 4G
   HTC Glacier (T-Mobile myTouch 4G)
   HTC Hero (T-Mobile G2 Touch) (Beta only)
   HTC Incredible S
   HTC Inspire 4G
   HTC Jetstream LTE
   HTC Legend
   HTC Merge
   HTC Nexus One
   HTC One S
   HTC One V
   HTC One X
   HTC One XL
   HTC Raider 4G LTE
   HTC Rezound
   HTC Rhyme
   HTC Sensation 4G
   HTC Status A810a
   HTC Thunderbolt 4G
   HTC Wildfire
   HTC Wildfire S 

Huawei

   Huawei CM980 (hwcm980)
   Huawei Impulse 4G
   Huawei M650
   Huawei Mercury
   Huawei U8651 

Kyocera

   Kyocera M9300 (Echo)
   Kyocera Milano (C5120) 

Lenovo

   Lenovo S880
   Lenovo S720
   Lenovo P770
   Lenovo P700i
   Lenovo K860 

LG

   LG G2X
   LG Lucid
   LG Marquee (LS855)
   LG Optimus Chat C550
   LG Optimus chat L-04C
   LG Optimus 2X
   LG Optimus 3D
   LG Optimus 4G, LTE
   LG Optimus Black (P970)
   LG Optimus G (E975)
   LG Optimus Hub LG-E510f
   LG Optimus Net Dual LG-P698f
   LG Optimus One KU3700
   LG Optimus One LU3700
   LG Optimus One Thunder P500
   LG Optimus One SU370
   LG Optimus Slider
   LG Optimus Z
   LG Revolution
   LG Spectrum
   LG Thrill 4G
   LG Optimus Q L55C 

Motorola

   Motorola Atrix 2
   Motorola Atrix 4G
   Motorola Cliq 2
   Motorola Defy
   Motorola Droid 2, Droid 2 Global
   Motorola Droid 3 (Milestone 3)
   Motorola Droid 4
   Motorola Droid Bionic
   Motorola Droid Pro (Milestone Plus)
   Motorola Droid Razr,
   Motorola Droid Razr Maxx (4G)
   Motorola Droid X (Milestone X)
   Motorola Droid X2
   Motorola Fire XT XT531
   Motorola Flipout
   Motorola Photon, Photon 4G
   Motorola Triumph
   Motorola XPRT MB612
   Motorola XT806 

MyTouch

   MyTouch 3G Slide 

MUSN

   MUSN M500 

Pantech

   Pantech Breakout 

Samsung

   Samsung Admire
   Samsung Admire SCH-R720
   Samsung Conquer 4G
   Samsung Continuum (i400)
   Samsung Droid Charge 4G LTE (Inspiration, Stealth)
   Samsung Galaxy 551 (GT-i5510)
   Samsung Galaxy Ace Duo GT-S6802
   Samsung Galaxy Ace GT-S5830/GT-S5358
   Samsung Galaxy Fit (GT-S5670, GT-S5670B, GT-S5670L)
   Samsung Galaxy Gio
   Samsung Galaxy Mini
   Samsung Galaxy Nexus
   Samsung Galaxy Next
   Samsung Galaxy Note
   Samsung Galaxy Note II
   Samsung Galaxy Pop
   Samsung Galaxy Pro B7510
   Samsung Galaxy Q
   Samsung Galaxy R
   Samsung Galaxy S (i9000, Captivate, Fascinate, Mesmerize, Vibrant)
   Samsung Galaxy S 4G
   Samsung Galaxy S II, 4G, HD LTE, X
   Samsung Galaxy S III
   Samsung Galaxy S Pro (Epic 4G)
   Samsung Illusion
   Samsung i8150 Galaxy W
   Samsung Infuse 4G
   Samsung Nexus S
   Samsung Replenish (SPH M580)
   Samsung Stratosphere
   Samsung T-Mobile Sidekick 4G 

Sharp

   Sharp ADS1
   Sharp SH8118U
   Sharp SH8128U 

Sony

   Sony Xperia S
   Sony Ericsson Xperia Arc
   Sony Ericsson Xperia Arc S
   Sony Ericsson Xperia Mini
   Sony Ericsson Xperia Mini Pro
   Sony Ericsson Xperia Neo
   Sony Ericsson Xperia Play
   Sony Ericsson Xperia Pro
   Sony Ericsson Xperia Ray
   Sony Ericsson Xperia X8 

Spice

   Spice Mi-350 

T-Mobile

   T-Mobile Move 

ViewSonic

   ViewSonic V350 

Vodafone

   Vodafone 945 (ZTE Joe) 

Wellcom

   Wellcom A89 

ZTE

   ZTE Atlas W (blade2)
   ZTE Blade (P729C)
   ZTE-C R750
   ZTE Skate N960
   ZTE X500
   ZTE V9
   ZTE Z990 

Tablets

Acer

   Acer Iconia Tab A200
   Acer Iconia Tab A500
   Acer Iconia Tab A510 

Archos

   Archos 101 Internet Tablet 

Asus

   Asus EEE Pad Transformer Pad Tablet TF101
   Asus EEE Pad Transformer Pad Tablet TF201
   Asus EEE Pad Transformer Pad Tablet TF300T, TL, TG
   Asus EEE Pad Transformer Pad Tablet TF700T
   Asus Memo Pad Smart 10
   Asus Google Nexus 7
   Asus Transformer Pad Infinity 

Axioo

   Axioo Picopad QGN 

Camangi

   Camangi FM600 

Cherry

   Cherry Mobile Superion 

Commtiva

   Commtiva N700 

CSL

   CSL Spice Mi700 

Dell

   Dell Streak 7 

HTC

   HTC EVO View 4G
   HTC Flyer 

Huawei

   Huawei MediaPad 7 

Lenovo

   Lenovo Ideapad K1 

Motorola

   Motorola Xoom 

Samsung

   Samsung Galaxy Tab 2 7.0, 8.9, 10.1
   Samsung Galaxy Tab 7.0 Plus
   Samsung Galaxy Tab 7.7, 10.1 

Sony

   Sony Tablet S 

Toshiba

   Toshiba AT 200
   Toshiba Excite 7.7, 10, 13
   Toshiba Thrive 

Viewsonic

   Viewsonic G Tablet
   ViewSonic ViewPad 7 

Wellcom

   Wellcom A800 

Other Operating Systems

For Firefox OS, see Get started with Firefox OS.

Firefox is NOT available for iOS (iPhone, iPad, iPod Touch), Windows Phone, Windows RT, Bada, Symbian, Blackberry OS, webOS or other operating systems for mobile.

mohammed.samad the OP asked about installing Firefox OS, not mobile Firefox.

https://developer.mozilla.org/en-US/docs/Mozilla/Firefox_OS

You will not be able to do anything with the Samsung Monte for starters as it is basically a feature phone that looks like a smartphone.

The Nokia 5800 XpressMusic is a old phone released back in November 2008 and has a 434 MHz ARM 11 cpu and with only 128 MB RAM / 256 MB ROM.

Thanks but I need a tutorial to revamp my old phones with a refreshing Firefox OS actually, not the Firefox browser.

Thanks for reply, Do you suggest any other ideas to make use of such old phones. As far as I knew Firefox was meant for feature phones utilising the power of web with minimal resources.

Does this mean, i cannot install firefox os never on windows phone. In future is it possible?