As reported by 9to5Mac, the app now harnesses a new feature that Apple included in iOS 10: Callkit. The offering enables third-parties to make their communications behave like standard phone behaviors. We've already seen this available to Android users, back in the days when Google merged Hangouts and SMS on Android.

Should other providers take advantage of Callkit, it's likely that people will gradually get used to VoIP calls behaving the same as their cellular equivalents. That, at least, will make it much easier for firms like Apple, Google and Facebook to gently elbow-out mobile networks' own products.