The iOS 15 update delivered new features such as Focus which is designed to reduce the number of time-wasting notifications, calls, and texts received on your iPhone so that you can focus on the task at hand. The feature also tells others not to bother you at the moment.
Another great addition to the iPhone in iOS 15 is Live Text. The latter discovers useful information inside your photos and online images. For example, if you have a picture of a sign that lists a phone number and email address, tap the former to make a call or tap on the latter to send an email. This will also work inside the camera app by pointing your camera at a poster, a sign, or something else that includes such information.
Several iPhone users with iOS 15 found that their touchscreen was not registering their taps
The adoption rate for iOS 15 was much lower than for iOS 14 after two days
This year, Apple allowed iPhone users to remain on iOS 14 and still receive security updates. In fact, unless you read the entire Software Update page, you might have missed the link on the bottom of the screen that started the updating process on your iPhone.