Image 1: screenshots of the user profile (admin view) on desktop and mobile.


The Tudu (to do) list is a tool to create and update lists of places you’ve been to or want to go to, with the possibility to add personal notes to each place, as well as ratings that don’t affect the places’ overall ratings. You can make each list public or private, then share your public lists with anyone you like, regardless of whether they have Tudu accounts or not.

The challenge

To conduct a heuristic evaluation of the Zara Mobile app and suggest redesigns to eliminate identified violations.

The team

Carolyn Cathcart (UX designer:, Funmilade Taiwo (UX designer: and me.

First, what is a heuristic evaluation?

It can be simply defined as a review of the app’s user interface, in order to identify app usability/user experience flaws. The evaluation is conducted against a set of design principles, also known as heuristics. They are called “heuristics” because they are broad rules of thumb and not specific usability guidelines. While there are several heuristics out there, for this project, we referred to Jakob Nielsen’s 10 general principles of interaction…

Image 1: Overview of the main navigation and filtering components, in desktop and mobile view.


Tudu is a Canadian startup created to help you find and share fun and unique things "tudu" (do to) in Toronto. Since September 2020 I've been leading the redesign of the web platform’s interface, by improving the look and usability existing pages and components, and creating new ones. The purpose of this this article/case study is to share with you part of my work thinking and designing a part of the website’s navigation, filtering and sorting components and interface.

Context is a child of the cool and popular Instagram page @ToDoToronto

Image 1: two screens (Dine & Drink and Filters) of the app, and a screenshot of the Marketing website's homepage.


I designed Citadin for my UX Design Diploma's Capstone Project. It's a mobile app that provides personalized recommendations of things to do and places to "dine & drink" near a user’s chosen location, using date, time, budget, interests, tastes and needs filters. The app allows users to plan their outings in advance and save experiences to their favourites, read other users’ reviews and leave their own. In this case study, I will take you through the journey of researching for, ideating and iterating the app until its final version, and share with you some successes and failures I encountered.

Image 1: two screens (home and loan repayment) of the app, and the overview page on the web platform.


I'm designing a VSLA digital solution to help SaCoDé facilitate 765 (and counting) Village Saving and Loan Associations spread across Burundi. As head of development and a designer, I will take you through a journey that begun with exploring existing solutions for the challenge SaCoDé is facing, and resulted in the design of high-fidelity prototypes of an app and a web platform. But this is just the beginning…


A Village Savings and Loan Association (VSLA) is a self-managed savings group, in which members…

Karl-Chris Nsabiyumva

Burundian living in Toronto | Dad, Husband, Entrepreneur, Storyteller & Product Designer | Tweep (@nsabiyumva_)

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