It's as simple as that. From everywhere in the world you can speak to visitors at the front door of your house. The build in motion sensor sees everything with it's 180 degrees angle. It can even trigger an alarm without the button being pushed.
Doorbird is produced in Germany, so quality is guaranteed!. Whether it is -20 or 40 degrees, or heavy rain, no problem for the Doorbird. It has a IP54 rating, which means that is is splashproof.
In this comparison you can see the Doorbird next to other intercom doorbells, click here to read it. The Doorbird has a better casing then the RING doorbell but is more expensive. Big advantage is that you can always use the camera remotely to check what is going on in front or your house, with RING you can only do this if you bell is connected to a power supply instead of batteries.