Resources
The proximity payment reference desk.
Guides, definitions, comparisons, and industry breakdowns for proximity identification and payment. The technology behind frictionless arrival, and the patents that protect it.
GuidesThe method, explained.Long form guides on proximity identification, the two channel method, and the short range wireless protocols behind it.9 guidesGlossaryThe vocabulary of proximity.Short, precise definitions of the terms behind proximity identification and payment, cross linked to the guides that use them.28 termsCompareThe method against the alternatives.Honest comparisons: the proximity method next to tap to pay, QR codes, geofencing, and direct device pairing.6 comparisonsBlogQuestions, answered.Answer first posts on hands free payment, robotaxi pickup, checkout free retail, and presence based identification.7 postsBy industryWhere the method applies.Industry breakdowns for rideshare and robotaxi, healthcare, retail, social commerce, and taxi safety.5 industries
Start here
Three guides worth bookmarking.
GuideHow do robotaxis work?A robotaxi drives itself with cameras, radar, and lidar, but the curbside handshake is unsolved. How proximity identification confirms the rider and the fare.10 min readGuideWhat is ultra wideband?Ultra wideband, or UWB, times a radio pulse to place a device to roughly ten centimetres. How UWB ranging works and why that precision matters for payment.8 min readGuideWhat is geofencing?Geofencing draws a virtual boundary and fires when a phone crosses it. How it works, why it locates coarsely, and how signal based proximity differs.8 min read
By industry
Where the method applies.
- Rideshare and RobotaxiThe pickup is the broken step. Your phone confirms the right car on approach, any robotaxi knows you, and the driver never learns who you are.
- HealthcareOne building can hold dozens of providers. The patient's phone finds the right one, payment routes itself, and the insurer gets a verified record.
- RetailJust walk out means no line. Because the system knows where the shopper is, loyalty acts at the moment of payment, not after the receipt.
- Social CommerceAn influencer's phone knows which product and room it is near. The platform sees it live, followers watch and vote, and the commerce layer follows.
- Taxi SafetyStreet taxis leave no record. Parousya notes the vehicle while the rider stays anonymous to the driver, and a family member can follow the journey.
Blog
Answer first, for search.
RetailWhat is cashierless checkout?Cashierless checkout lets you take what you want and walk out, with no register. The hard part is knowing who is paying. Here is how it works.March 31, 2026 · 6 min readSecurityIs tap to pay safe?Yes. Tap to pay uses tokenization, so the terminal never sees your real card number. Here is what protects a contactless tap, and where it can go further.April 14, 2025 · 6 min readTechnologyNFC vs Bluetooth: which is better?Neither. They solve different problems. NFC is a deliberate tap at a few centimetres. Bluetooth reaches across a room. Here is how to choose.December 20, 2024 · 6 min read
Licensing
See your industry in the method?
We license the Parousya method to companies building where proximity and payment intersect. If you can see an application, we would like to hear from you.