Apple already used the 3D force touch technology in iPhone 6s and also implies in iPods and now the technology has to be more refine and for that company engineers are work on them but it is the time-consuming process and need a scalable version of the device to be work fine. So it is expected that the upcoming iPhone 7 and iPad Air 3 will not feature with the modest version of 3D Force Touch because the hardware is not compatible with the current version of 3D touch.
The implementation of 3D force Touch make the application usage more useful and increases the utility of functions so Apple tried to add more apps in their upcoming iPhone for more efficient working and apps functionality and for testing the modest version of 3D touch engineers need a large display because the technology needs the properly scaled system for proper function and performance. So the Apple works on the latest version which is compatible with a large display such as 12.9 inches seeing in iPad Pro. Though upcoming iPhone will not be revealed before 2016 but making the technology more perfect requires more time.
Just for the sake of users, the iPhone 7 will come with 5.2 inches display. The device runs iOS 9 and features with Dual-core 1.5 GHz processor. The device has 2 GB RAM and 64 GB internal memory and equipped with 12 MP rear and 2 MP front-facing a camera. In the design line, it is expected that the iPhone will come with metal and glass. If the rumor becomes true then it will be the costliest device than the previous models of iPhone. All of the information need to the confirmation from Apple and we need to wait long for that.