TAP cards have been around for a while now, but there seems to be very little information around that explains how they work, particularly by the LA transit system.
Here is an article saying that they are set to replace the MetroCard for the New York transit system with TAP:
The official Transit Access Pass website has this to say:
Each TAP card has a built-in electronic chip.
It’s like a mini-computer inside your card! It lets you load Stored Value (money) and a variety of passes for travel across 24 transit agencies. No more fumbling for change. Just load the type of fare you want on your card, then tap it each time you board a bus or train. It’s way faster than cash!
It is some sort of contactless smart card, but looking around using that as a search term, TAP seems not to be listed as using the ISO 14443 standard. Yet maybe it does.
Question: How do they work?