Hey iordanis2 , nice to see you here , you are developing the apps for mobile devices using different browsers , if you want to have an emulator for windows to run firefox android on windows , you can download the emulator named "BLUE STACKS " which is used to run android apps on windows. It can run almost all android apps on windows. Here's the link for it :- http://www.bluestacks.com/download.html?utm_campaign=siakbary Also you will need an ".apk" file of firefox to run it on windows through bluestacks , you can get it from here :- [admin: edit] https://archive.mozilla.org has Mozilla Firefox for direct download. And as you are a developer , firefox is open source so you can also look onto it's source code . You can go through them if you want and also you can use it , you would have to find it here :- [admin edit] the cannonical url is https://hg.mozilla.org/mozilla-central/ Thanks for being here. Regards:- Gaurav(gaurav1999)