Meet the FlexiBell: a doorbell that uses a SIM card to call you when you have a new visitor. It does not require a cloud service or app to work. You will be able to talk to your guests from anywhere. The FlexiBell is compatible with all smartphones and most smart locks on the market. It is pretty easy to install, which helps.
More gadgets like this: here
More information is available on Indiegogo.
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