Coven: a Case study of a Smart oven app

Designing a mobile app that controls a smart oven

Coven: control your microwave oven from your mobile phone with ease

Product name: Coven

Role: Product designer

Time frame: 2 (two) days


“ … Can you come up with … and an App only oven. The oven is controlled only by the app, and has no buttons or handles”

Defining the product

To kickstart the project, I started out with trying to understand the context of the existence of the product

This involved interviews with the stakeholders to understand their goals and objectives for the product, for this project I coerced some of my friends into being the imaginary stakeholders 😁.


The goal of the product is to allow users to control the oven entirely from the app.

After this, next was to try to understand the user problems the Noven app was trying to solve and I came up with the following:

  1. For people who are busy with other things.
  2. For people trying to cook conveniently while carrying out other activities.


Market research

I continued with a bit of quick market research to check out similar competitor products to get a quick understanding of the smart oven domain, what I can replicate and improve on in Coven and how they approached the creation of their products. Prior to this project, I had heard of smart ovens but it was strictly basic information. Ovens are so advanced these days, some can self-clean and even have intelligent humidity sensor 😮😲.

User research

Now that I had a little bit of knowledge of the smart oven domain I went back to my user to really trying to understand who the user could be, what they want and how they would use the app hypothetically.

I assumed that the user knows what he/she wants to cook and decided that there are 3 stages involved in cooking with a microwave oven:

  1. Getting ready to cook.
  2. Cooking.
  3. Finish cooking.

Each of these stages would match how the app flow should work.

Creating Personas

The personas I created were personas modeled after my friends. The goals, needs, and pain points are actual responses from a sit-down interview with them.


Ayomikun, my primary persona was created by combining the other personas into one. So I guess I can say Ayomikun is a compound persona (if something like that exists) 😎

Ayomikun “The compound persona”


Based on insights from data collected during the research I was able to capture, organize and make inferences from the results of the user research. These inferences gave birth to the primary features and user flows of the app.

Product Features

  1. Timer
  2. Temperature controller.
  3. Food type presets.
  4. Different operation modes e.g. Preheat, defrost, bake and grill.
  5. Sensor monitoring for Humidity control (prevents meals from being overly dry).
  6. Power saver mode (reduces power consumption).

User Flows

This involves flows that would cover all the stages covered in the discovery process. I created user flows for two particular tasks.

Task 1: Defrost chicken

The user flow for this task illustrates the steps involved using a particular food type preset (chicken) and a particular operation mode (defrost).

User flow for “Defrost a chicken” task

Task 2: Cook a meal

The user flow for this task illustrates the steps involved in cooking a meal without selecting food presets or a mode but rather by specifying the time and temperature.



I created the sketches as approximations of what the final product might be and used it for user-testing.

low fidelity sketches

Mid-fidelity mockups

I used feedback from the low-fidelity sketches to work on iterating the design of mid-fidelity mockups. I used the mid-fidelity mockups to establish hierarchy and have a clearer layout.

High-fidelity mockups

From Left to Right: 1. Welcome screen. 2. Connect screen. 3. Connected screen.
Left to Right: 1. Select mode screen (presets). 2. Select mode screen (manual). 3. Ready screen. 4 Status screen.
  1. Welcome: Landing screen. Clicking on “get started” takes you to the connect screen.
  2. Connect: This screen instructs you to connect your phone to the same WiFi network as the microwave oven. I assumed the microwave oven is already connected to your WiFi.
  3. Connected: This screen shows the connection status between the phone and the microwave oven. Clicking on “continue” or “cook” in the navigation bar takes you to the select mode screens. Since it is stated in the project brief that the oven neither has handles nor buttons, I decided that the oven uses sensors that allow it to know when you are about to place food in it, in conjunction with the signal gotten from clicking “continue” or “cook”.
  4. Select mode (Presets): Choosing presets allows you to choose a mode of operation and food type without having to worry about setting time and temperature, then automatically starts cooking.
  5. Select mode (Manual): Manual allows you to set temperature and time, after which you click on “cook” to start cooking.
  6. Ready screen: Clicking on “remove food” opens the door of the microwave oven and puts the microwave on standby.
  7. Status screen: This screen is like a dashboard, it shows the current status of the microwave oven and has toggle switches for the humidity sensor monitor and power saver.


I created a very simple clickable prototype with Adobe XD. I omitted some in-between states that I would have liked to add due to time constraints (2 days). 😅

Go to prototype

Testing and Validation

I carried out scenario tests to validate that the design was traceable to the aim and user flows created for every fidelity level of the design.

Here is an example of feedback from the low fidelity sketches user testing session:

For some reason, I find the method of setting the time and temperature weird. Can you look into it?

This feedback prompted me to inverse the methods for setting the time and temperature to what it is in the high-fidelity mockups.


I made some assumptions when designing the app:

  • Users will be early adopters of new technology
  • Users will only be able to communicate with the microwave open via the app on their phone — no Alexa, Google Home yadda yadda.
  • Users just want it to work so they can cook, they are not concerned with sensors and all that.
  • The microwave oven is always connected to the WiFi of the user. The Bluetooth connection would have been the easier option but I felt Bluetooth has the tradeoff of having to be in close proximity to the microwave oven.
  • I assumed the oven is a microwave oven 😉

What could be next

What could be the next steps to take if this project was actually real?


  • How do I cater to the blind?
  • How do I account for the different ways people know their food is ready (tasting, tenderness and all the 1 million humans know their meal is ready 🙄)
  • What happens if no internet available (Bluetooth ?)
  • What metrics can be tracked to show the product is successful?

Idea basket:

  • The oven identifies food by scanning the barcode and can check for recipes online.
  • The oven “talks” to other connected appliances and can re-order or order certain foods based on consumption and recipes
  • The oven starts to learn how you like to cook different foods and adjusts over time to your preferred cooking style
  • How could this work with a wearable such as an Apple watch (almost everyone has one nowadays)?

I really had fun putting this together in two days. This project was a design exercise as part of my interview for a Product designer role. I hope I get the job 😉