Just bought the Ring.com video door bell and I like it! If you have not heard of this device, what it does is sends a notification to your phone whenever someone rings your doorbell or comes within close proximity of your front door. The notification allows you to see them on video and talk to them straight from your phone.
We went on a trip to another state and I was able to talk to guest when they were talking outside my front door. They were shocked. For a small fee of $3/month (or $30 for the year) you can have Ring.com save the video footage. This would come in handy if someone was at your door doing something they were not supposed to be doing.
There are a few issues I have with the device. It does not allow you to see your front time on demand. Meaning, you cannot hit a button and see what is going on. Someone has to be trigger the motion detection or ring to doorbell in order to be prompted to see what is going on. Also there was a vulnerability in the ring.com software that was had the secret key of your wifi network unencrypted, but this was fixed by ring.com as soon as they discovered it. The other thing I have an issue with, is the lag. There is like a 5+ second delay from the time the system is activated to the time it gets to your phone.