If you’re like most people, you probably have an iPhone 4. But if you don’t, there are a few things you can do to upgrade it to iOS 9. First, go to the Apple website and sign up for a subscription to the Apple Developer Program. This will give you access to some of the latest beta software for your iPhone 4. Second, download and install the iOS 9 beta software from Apple’s website. Once it’s installed, open it and click on the “Beta Software” tab. Third, open iTunes and update your iPhone 4 to iOS 9 by going to the " Updates" tab and clicking on the " Update Now " button.
