how to detect beacon signal and do we need to make any app to manage it or any predefined app or site is available? I want to know how Beacon works and which Beacon is suitable for retail.
You need a mobile phone with Bluetooth 4.0 to detect beacons. They emit a BLE signal which is a little different from the normal Bluetooth signal. There are many generic apps in the play store and maybe in the app store to detect them. But if you are looking for real functionality related to that, then you'll be needing the retail store-specific mobile app so that it can show you relevant updates in the app.