The equals sign means is equal to. It is telling us that one thing equates to another; that they are the same.
The iPhone 4 is the most recent iPhone to be discontinued from the iOS Update cycle. It did not receive the iOS 8 update, so it's final software version is iOS 7.1.2. You can update to this version through iTunes, or download it from an IPSW repository like this website: https://ipsw.me/.
Apple announced the iPhone X last week. You can preorder the iPhone X, Apple's highest-end iPhone, on October 27 from Apple's website. It will hit retail stores on November 3. It's got a strikingly different design, featuring a new screen that covers nearly the entire front of the phone. It's also got new cameras, sensors, and has better battery life than the iPhone 7. Tim Cook announced the $999 iPhone X at a September 12 keynote at the newly unveiled Steve Jobs Theater Getty Apple and investors hope that the iPhone X can propel a super cycle of sales that returns the Cupertino company to revenue growth. In 2016, Apple reported $215 billion in sales, its first year-over-year decline since 2001.