Hello!
I bought recently a Smartlock Ultra + FOB for a house, I only have one street door and three floors.
My idea was to use three FOB’s, one on each floor to open the door when a guest arrives to substitute the intercom.
But FOB it’s extremely slow (5-15seconds) and it only works in the first floor.
Is there any way to use a Wifi button for this? I searched a lot and I cannot find any simple way to do it, I don’t want to have any local server only for this situation.
Thanks! 
If you can find a Wi-Fi button—similar to the discontinued Shelly Button 1—that supports HTTP POST requests, you could use the Nuki Web API to unlock your door with a single press and without the need for a local hub.
Thanks for your answer!
Correct me if I’m wrong but I thought HTTP Post request no longer worked on the newer models (Pro and Ultra).
In that case I cannot find how to activate it, it would be simpler and use a simple (and cheap) esp32 with a button
You are referring to the bridge API, which is only available for products that are connected to a Nuki bridge and the latest generation of Smart Locks is not compatible with the Nuki bridge anymore.
However, the Nuki Web API works with every product that is connected to Nuki Web and therefore with any generation of Smart Locks.