Coby is a smartphone application whose goal is to simplify group purchases. When making a payment, both in store or online, the user and the merchant create a new shared temporary wallet. The game begins and the user invites friends to join the wallet, collaborating with him to achieve the payment. The sooner they join, the more points they get and the more people joins, the more everyone saves. When the time is over, the payment is transferred directly from each participant’s account to the merchant’s one.

This concept takes money and payments to a complete different perspective where a payment is a group task and collaboration between users is fundamental. Timing is very important too because it leads to a better placement in the leaderboard. “To pay” is something nobody likes, by making it playful and fun people have a strong compelling reason to do it. This solves one of the biggest issues in the usual process where emotions are often involved, making people look stingy, breaking friendships and relationships when a user doesn’t pay back what he owes.

The usual process is divided into three steps:

a) One user makes the purchases, paying in advance for everyone

b) The user calculates the splitting costs and communicates them to the participants

c) Every participant pays back the user

There are multitude of softwares and technologies in each of these areas. Many, like Apple Pay and Android Pay are trying to make money fading by putting a digital version of the traditional wallet in the hands of users, creating a contactless purchase experience. Others help users to split the costs, like Splitwise, while others like Venmo and Facebook are introducing person to person (p2p) transactions. None of them are solving the group purchase in an effective way. Coby solves the problem at the root, making a three step process simpler and quicker in which every user pays directly to the merchant twentyfour hours after the purchase.

Interface and interaction modality

Coby is a smartphone application. The project outcome is a prototype based on Marvelapp which can be enjoyed on a browser or installed on Android using the attached apk file.


The tool used to design the UI is Sketch by Bohemian Coding. Micro interactions and animations are designed in Adobe After Effects. The prototype is based on the Marvelapp service.

User experience

The UI has been designed in order to convey the concept pillars, therefore the look and feel is playful and joyful but in the same time simple and clear. The navigation pattern and UI layout create an atypical experience in usability, which is coherent with the “different perspective” pillar.

Research and development context

Coby could be further developed in many ways but the most promising seems to be the integration with existing payment options like PayPal. They have many common aspects and could be complementary each other.