The conversation between human and AI assistant.
How can I update my iPhone 4S from iOS 7 to iOS 9 for free?
Can you tell me how I can update my iPhone 4S from iOS 7 to iOS 9 for free?
Yes, I can. Firstly, make sure your iPhone 4S supports iOS 9. Then, connect your iPhone to Wi-Fi, go to Settings > General > Software Update. You should see the iOS 9 update available there. Just tap "Download and Install", enter your passcode if prompted, and wait for the update to complete.