Interaction Observation

Published September 27, 2017

Point of sale interactions – and the systems which facilitate them – are among the most impactful and unfortunately boring interactions we have with technology on a day-to-day basis.  They are impactful because we use them for nearly every financial transaction at a store or restaurant and their usability (or lack thereof) affects our impressions of the vendor vis-a-vis trust, competence and ‘coolness.’ They are boring because their ideal state is one of being unnoticed.

Within my lifetime, I have used dozens of different POS systems: from traditional non-digital cash registers to a variety of card readers – manual entry (replete with flatbed printer), ’square’ style credit card readers or modern chip insertion readers. Within these different types of card readers, I have used dozens of different individual systems, and while each of them shares the same basic series of operations, the way these operations are broken down into steps for the customer and teller varies from one to the next.

“Gregory” Coffee App Payment:

Most recently, I have used the phone-app based payment system by the coffee shop Gregory, in which payment information is displayed on screen in the form of a QR code which is read by an accompanying reader at the coffee shop locations.

The use of this app involves the following steps:

  1. Before paying, the customer loads the app, which displays a large QR code on-screen.
  2. Below the QR code is a slider which indicates tip percentage, and can be slid from its “home base” of 0% to 10% and above.
  3. When the teller has finished taking your order and asks for payment, the customer faces their phone screen toward the corresponding reader on the counter.
  4. The reader has a strip of acrylic running around the perimeter, illuminated by a blue light. When the reader has picked up the payment information, the light changes to green to indicate payment information has gone through.
  5. The app gives a notification of payment including amount. If set up, it also emails this information to the customer.

The entire interaction (less the actual order-taking) takes about 10 seconds at most.


I have used this system for a number of months — having been convinced to download the app by the promise of a free coffee. I had avoided these systems (which exist in many forms at many different coffee shops) since their introduction a few years ago because I feel they attempt to obscure spending and encourage less-conscious consumption through ease-of-use. My experience with the Gregory App has not disavowed me of this belief, but it is convenient:

  • It allows me to keep my wallet in my bag rather than my pocket.

  • It requires no signature.

  • It allows tip to be pre-set and retain that setting from transaction to transaction

My observations of other customers’ use of the app has revealed that:

  • Very few customers actually use the app rather than a credit card or cash.  I spent half of an hour in the coffee shop during a morning rush-hour and I was the only one who used the app and,

  • Of those I’ve seen use the app in the past, most seem to be seasoned professionals at its use.  Because the app is specific to Gregory, the only ones who use it are those who frequent this specific shop (rather than a generic payment system like Apple pay).  I suspect the limited scope is what makes the system simple to use.

  • The system requires tellers to enter the price twice – first they calculate using the iPad based cashier app and second they enter that price into the POS systems small keypad.  While this is a fairly small task, it is an example of a technology shifting responsibility to the employee because the two systems – the iPad used for most transactions and the QR code system – don’t play well together.