How do I update my device

Your iPhone 6S Plus can be updated to iOS 15.7.3

If you are already on this version, your iPhone cannot be updated further. However, it is not impossible that Apple releases a security update for iOS 15, you will also receive it. But you can't update to iOS 16.

You can check your current version here:

Settings → General → About

You can download and install software updates here:

Settings → General → Software Update

Remember to connect to Wi-Fi and a charger. Your iPhone must have more than 50% power to update without a charger connected.

You can find more useful information here:

Update your iPhone or iPad - Apple Support

If your iPhone or iPad won't update – Apple Support (UK)

If you want to update your iPhone via a PC or Mac, see here:

• Mac: Update your iPhone, iPad, or iPod touch with the Finder - Apple Support
• PC (iTunes): Update your iPhone, iPad, or iPod touch with iTunes - Apple Support