This model is Gen 2 and this model has not door sensor. Gen 3 model is same price but Best Buy don't have gen 3 only version. They have Gen 3 with wifi point set model only. If you have iPhone and Apple TV (4th gen) or leave your iPad home, you could use HomeKit so you don't need to buy wifi point. But if you want this function with non apple smart phone like android, you need wifi point. The retrofit version is cheaper 3rd gen and it has door sensor but it does not compatible with HomeKit so you need wifi point if you want to use function of lock and unlock everywhere.