Demo Transit Validator application is part of overall demo version of public transit fare collection system World Wide Open Fare that can be characterized as Open Loop Account-Based system. The architecture of World Wide Open Fare provides good patron experience for debit card holders.

The entire demo system is described here: https://wwopenfare.com/demo-version/
The app emulated fare collection and trip validation device mounted on a bus. You can install this app freely. It is free and safe. To use the app, you need to follow the procedure described at the aforementioned link.

The app emulates a bus moving along a bus route with certain stops. The “patron” taps a payment card (Visa, Mastercard, etc.) at the current bus stop and is allowed or not allowed to board the bus depending on the fare collection and trip validation logic.
Many validation logics and fare calculation logics are supported, such as flat fares, distant based tap-on/tap-off fares. Transfer discounts may be applied when configured