Although the actual implementation of the 3D Touch is somewhat problematic, the approach taken to the functionality assigned to this feature is the correct one: 3D Touch should be an enhancement to the user experience, not a requirement to achieving a user task. Indeed, so far, all the functionality provided by 3D Touch, whether in quick actions or peek-and-pop mode, is redundant: users who don’t have the latest iPhone or have trouble with the 3D Touch can still do their tasks without using it and achieve the same kinds of actions, albeit in a more roundabout way. This redundancy is the right solution to the problems that gestures pose: lack of affordance and memorability, as well as difficulty in performing them.
Great in-depth analysis of 3D Touch by Raluca Budiu, Nielsen Norman Group. Adding a whole new dimension of interaction can be a double-edged sword, but Apple seems to have nailed it by encouraging the adoption of microsession-oriented patterns focused on efficiency, like “Quick Actions” and “Peek and Pop”.via nngroup.com