Design Critique : Duolingo (android app)

Duolingo is a free language education app, giving everyone access to a private tutor experience. It’s available both on iOS and Android and also in the web browser. The following critique is focused on the android app, inspired by reading Donald Norman’s book ‘The Design of Everyday Things’.

Let’s begin

As soon as you open this app, the users select the language followed by a question as if you are a beginner or not. The app operates as per adaptive learning, giving you a level of assurance that you will learn new things. After picking a goal you would get dropped into the first lesson. “Play before” and then “create profile” approach is efficient for learning apps.

In the Game

It’s hard to stay motivated while learning online and Duolingo makes learning enjoyable like playing a game. The flag on the top left corner (fig1) is a signifier indicating the language being currently learned. It’s an easy visual cue if you don’t want to read. After clicking on the flag, a menu—​ a list of choices on a temporary surface—​appears (fig2), displaying all the flags of the languages that are being learned, followed by an add “+” icon. The conceptual model of that icon makes it an appropriate signifier by recognizing the user’s action to discover a new language. We know from knowledge in the head (existing learning in the human memory) that the app affords learning various languages. Conceptual model of lists (fig3), additionally with natural mapping, the user knows that the  index of language affords scrolling. The ellipsis “…” icon and the distinct copy “more” on the call-to-action button (CTA) makes the language choices discoverable. There could be a better way to show an array of languages as the list can get quite long. Adding the functionality of searching the languages will enhance the experience.

Level up

As the users advance through their journey the program steers towards numerous signifiers. Each topic has its own progress bar, signified by the completion of the yellow color inside the circle and the number denoted in the crown icon. The users can understand that the screen affords scrolling as only some part of the upcoming topic are visible (fig1). The disabled (greyed out, fig4) topics, signify that they have not been started yet. When the user clicks on the topic “Checkpoint 1” the app gives an immediate visual feedback, telling the user what they have to do in order to access that topic. According to Don Norman’s book, this design is intuitive as it guides the user instead of blocking their action without explanation. Another element making this design user friendly is the use of physical constraints to aid learning in an organized format rather than showing all possible topics at the same time.

The progress functionality on individual topics does not have a signifier telling us how much content is left to complete that topic. Don Norman mentions, bookmarks in books being used as signifiers and how they prompt the users, by letting them know how close they are finishing the book. “Basics 1” (fig1), shows that the user has gone through 4 parts of that topic, but the information telling how many levels are still left is not mentioned upfront. The copy here could indicate that the user is at level 4 out of 6 total levels for better flow of information.


Duolingo analyzes how people learn, and they are trying to build the most effective educational system possible and customize the experience. Users come with different proficiency, they are inclined towards learning the language. In the words of Marie Kondo, this app does spark joy.