Some iPhone owners must have noticed this when you receive a call; some people get an option of “accept” and “decline” buttons, whereas others simply have a “Swipe To Answer” slider!
The question is, why two different options for the same function?
One might think that this might have to do with the iPhone model of the caller, or the caller using the phone other than an iPhone. But as it turns out, it only depends on the type of the recipient’s phone!
The difference is between an unlocked screen and a locked screen. If you are using an unlocked phone (screen), no matter who’s the caller, you will get two options of either rejecting or accepting the calls. Whereas if your phone screen is locked, you can either slide it to accept OR you can reject the call by pressing your volume down button twice.