That’s all thanks to the system’s real time two way audio feature, with its built in microphone and speaker. The VueBell WiFi HD Camera Video Doorbell also comes built with a motion sensor technology called Smart Guard Function that triggers an alert and sends real time push notifications, along with a snapshot, to your smartphone or tablet. This is triggered whenever motion is detected or when someone rings the doorbell or have not pressed the button. This gives you peace of mind knowing that you’ll immediately be notified each time something untoward takes place at home, or when a person comes over to visit, while you’re away. PROS:Budget friendlySleek and compact design720p HD resolutionExtra wide field of viewSuperior night vision featureHas pan/tilt capabilityMulti user sharingSmart Guard Function motion detection + snapshotTwo way audio featureCloud storage supportCONS:Must be connected to an existing doorbell wiringNo support for local storage6 Xenon WiFi Doorbell Security Camera ProductDealsLast reviews The features of Xenon is easy to install,cheaper than other seller, can control by your phone,night version and PIR function. It is the best cost performance.