These types of methods are often attempted to be used for payments but theres a bunch of practicalities in rolling them out that hurts adoption. Id say the eas

These types of methods are often attempted to be used for payments but theres a bunch of practicalities in rolling them out that hurts adoption. Id say the easiest is to give them an app where they can check their credits and geofence the yoga class so a push notification appears once you arrive. If you really wanted to, you could display a TV displaying a live page on your website and when the geofencing is triggered it will display the persons details.