This web site uses cookies to improve your experience. By viewing our content, you are accepting the use of cookies. To find out more and change your cookie settings, please view our cookie policy . Close When it will officially reach your handset will depend on when your network gets around to rolling it out. Are you too impatient to hang around for them to pull their finger out? If so, we're here to help, with this guide on how to install a straight-up Jelly Bean ROM that's lovely and stable on your Galaxy S3. 1. Root your Galaxy S3 You've already rooted your phone, right? You won't get very far if you haven't. To install a custom ROM (which is what we're doing, going behind our networks' backs and all), requires root access to the phone. In layman's terms, that means we free ourselves from manufacturer restrictions and wrest full control over it -- so get ready to ride without stabilisers on your Android bike. We wrote a big old guide on how to do that here . Just make sure you're using the I9300 model of the phone, otherwise you risk turning your S3 into an aesthetically pleasing paperweight. You can double check that by going into your 'About Phone' section in Settings and scrolling down to see the model number. 2. Let's find a ROM Next up, we need a suitable ROM to bring sweet Jelly Bean treats to your phone. We'll be doing a round-up of