Supporting ideation and collaborative design with location-based smart contracts

Geocoins: Bodystorming the BlockChain

As part of the After Money project, Design Informatics developed of a piece of software called ‘GeoCoin’ that served as an introduction to what programmable currencies could offer in a technical sense, but also allow participants to test them in an urban context to support the development of their own ideas. ‘GeoCoin’ was a mobile application run from a web browser that used location information to pinpoint the participant within a map of Nieuwmarkt area of Amsterdam. Using the Bitcoin client Electrum, we were able to associate geofences (GPS locations) with transactional functions. On the map the participant was also able to see three types of icon: small bags of money scattered across the area, red hot spots, and green hot spots. In the corner of the bottom left corner of the screen two numerical amounts appeared preceded by the terms: Confirmed and Unconfirmed. Without further information, participants were asked to leave the workshop studio and venture out in to the surrounding area to discover what the three icons and the numerical values would do as they approached them.

Browser screen shot (with location on) of the GeoCoins software featuring bags of coins, and red and green GPS hotspots.

Once outside, it became relatively clear to people that the small bags of money would disappear when a participant’s location correlated with the GPS coordinates of an icon, and within moments the Unconfirmed number would increase on their screen. On returning to the studio participants described their interpretations of how the red and green hot spots worked, and why Unconfirmed and Confirmed numbers fluctuated. Many had guessed that we had used a digital currency such as Bitcoin and distributed fractions of them across the landscape. Less easy to understand, because there was no instant feedback from the icons (unlike the bags of money that disappeared as you walked over them), the group began to realise that if their location corresponded with the GPS coordinates of a red hotspot then their Unconfirmed numbers would decrease, and that if they stood on a green hotspot their Unconfirmed numbers would increase.

Gerd Kortuem running to pick up a bag of Bitcoin (before I did!).

Whilst these elements were relatively easy to understand, the question of why numbers across the Unconfirmed and Confirmed lines fluctuated was less comprehensible. The difference in the two variables was explained as being the time it took for the blockchain to ratify a transaction within a block. At this point the value of experiencing the time between Unconfirmed and Confirmed transactions began to expose some of the characteristics of a currency that requires confirmation through an entire digital network. Body storming the type of transactions that a programmable currency such as Bitcoin offers was an important step in supporting participants towards the design of their own derivations of the software, and based upon the results, the ability to perform economic software within an urban landscape informed both the conceptual development of ideas but also the representations of their work.

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Blog originally posted on Chris Speed’s website