Hi, actually were not using webcams at all. We using real eye trackers. Commercial eye trackers are becoming cheaper (eg. $99 see https://theeyetribe.com/) and even the bigger eye tracking companies such as Tobii and SMI are starting to make low cost eye trackers.
Tobii, which is partly owned by Intel, has also already developed laptops that have eye trackers intergrated
Tobii, which is partly owned by Intel, has also already developed laptops that have eye trackers intergrated