Why is this, you ask? According to the folks at ArsTechnica (via 9to5Mac), it seems that iOS 10.3 has included a fix in which it will patch a security hole in Safari that allows hackers to take control of your browser, and in return demand ransom before it is released back to the control of the user.
Prior to iOS 10.3, the issue could be dealt with by clearing the browsing history and the cache, but we guess this is something that not all users might be familiar with. So with iOS 10.3, Apple has basically closed the hole so that hackers will never be able to pull this hack off again, thus making life a bit safer for iOS users on Safari.
Researchers at Lookout have detailed the vulnerability, but like we said with iOS 10.3 Apple has since patched the problem, so maybe you’ll want to update just to be safe. The update also brings about new features like Find My AirPods and also allowing users to leave in-app ratings.