FlexiBell: Answer Your Door From Anywhere

Meet FlexiBell: a handy tool that lets you answer your door from anywhere on your smartphone. You receive a call when you have a new visitor. There is no cloud service involved here. You will be able to accept guests and communicate with them no matter where you are.

FlexiBell is compatible with all phones on the market. It also works with electric locks and automated gate systems. Yet another interesting Indiegogo project.