Beacon to reveal presence in a Shop

We are developing an app in android and we thought we could detect with only one beacon the passage of people through a store door to enable features in the app only to those in the store.
We checked with the beacons in our possession (Proximity beacon) and found problems with signal instability even in the absence of obstacles.
Our ultimate goal is that through beacon some app services work only in store, can it be done with only one beacon positioned on the entrance and exit door from the store?

Hi @michele1968sa,

don’t you think you could use the monitoring technology to constantly check if the customer is inside rather than checking at the door?
For example, you put your beacon in the middle of your store (if the place is not too large), and the app’ on the phones monitors your region in the background to notify when the customer entered or exited the store.