For your info Javascript is not something you can install, its client side scripting language used in website to do things in website without sending requesting to server, its also used to create wow moments in deign and other purposes. You need not install java script its automatically downloaded form the website you visit. I see that your are not using firefox for android phone, so i cannot detect whether your browser supports Javascript or not (not all phone support Javascript mainly low end phones cannot support them). Hope you got your solution, do ask if there is any thing else you need.