If you've been having touchscreen problems with your iPhone 6 Plus, Apple has a fix for you if you're willing to pay for it. The "iPhone 6 Plus Multi-Touch Repair Program" is for phones that are either having trouble registering touchscreen input or that are have flickering displays as a result of "being dropped multiple times on a hard surface and then incurring further stress on the device."
Unlike past iPhone repair programs—a list which includes the power button and battery in the iPhone 5 and the camera in the iPhone 6 Plus—Apple is charging a $149 service fee to replace iPhones affected by the problem. Even then, Apple says your phone needs to be "in working order" and can't have a cracked or broken screen. If you have previously paid for a repair related to these problems, Apple says that you can contact the company to be reimbursed for whatever you paid beyond $149.
Based on Apple's description of the problem, it sounds like this could be a fix for a problem that iFixit and independent iPhone repair shops brought to light a few months ago. Colorfully dubbed "Touch Disease," iFixit says that the problem is caused by touchscreen controller chips that can come loose from the logic board. The controllers in question were moved from the logic board into the display assembly in the iPhone 6S, which iFixit speculates is the reason why later variants of the iPhone 6 design aren't susceptible to the same problem.
Source: ars