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/.
The history of smartphones: timeline. January 2007. Steve Jobs, chief executive of Apple, unveils the iPhone, which he says is a revolutionary and magical product that is literally five years ahead of any other mobile phone. Microsoft chief executive Steve Ballmer calls it the most expensive phone in the world.