How Do I Install iOS 9 on My iPhone?

How can I update my iPhone 4 to iOS 9?

Upgrade to iOS 9

1. Make sure you have a good amount of battery life left. …
2. Tap the Settings app on your iOS device.
3. Tap General.
4. You’ll probably see that Software Update has a badge. …
5. A screen appears, telling you that iOS 9 is available to install.

How do I upgrade my iPhone to iOS 9?

Update on your iOS device

1. Launch the Settings app. From your home screen, find your Settings app, and tap on the icon. …
2. Go to “Software Update” From the “General” screen, tap the “Software Update” button.
3. Download and install the update. …
4. Finish up.