In times it gets difficult to navigate to the deep settings and enable/disable the automatic answer option for incoming phone calls, there’s a small application you can use to make your life easier.
myCar Profile allows you to easily activate or deactivate automatic answering of phone calls as well as turning speakerphone on or off. There’s also an option to set the number of seconds after which auto answer occurs (make sure the number is less than the number of seconds the call gets diverted to voice mail). In order to do this, myCar Profile needs to be running in the background but a two step procedure seems easier than going to Start, Settings, Personal, Phone, More and check Answer incoming calls without pressing Talk.
(Source: XDA Developers)