HCDE 451 A5: Video Prototype— Lifesum

Michelle (Xin) Gao
4 min readNov 12, 2019


Making a promo video for the Lifesum, a food tracker application


The design for this week is to create a 60s video prototype that demonstrates the functionality of a product. We are limited to only pick health or fitness related products. So I decided to make a product promo for the Lifesum mobile application. I chose this app because I have a doubt about the method that losing weight by controlling the daily energy intake. Therefore, the feature of a calorie counter grabbed my attention and then I decided to go with this app.


Background information: The main character Michelle is in the process of losing her weight. She uses an app called Lifesum to help her achieve the goal. Based on a series of calculations done by Lifesum, Michelle’s daily energy intake is restricted to 1330 kcal/day.

Scenario: The scenario for the video begins with Michelle looking at a menu in the coffee shop, trying to figure out what to have for dinner. She plans to have the chicken salad, but before actually ordering it, she needs to check how many calories she should have for this meal. The app tells her that she should take in no more than 545 kcal. Double-checking with the waitress whether the salad is in the allowable calorie intake range, Michelle decides to order the chicken salad. After the food is offered, She takes a photo of the food and uploads it to the Lifesum app. She is using this app to record what kind of food she has eaten today. The app provides a list of food categories based on the photo, but the list is not complete. So Michelle manually inputs the information of the food such as chicken straps (I mistakenly said “chicken salad” in the video) and 2 cups of water. The scenario finishes with the app tells Michelle that she has achieved her goal and doesn’t overeat today.

Storyboard based on the Scenario


What Worked Well

  • the story
  • the background music
  • Transition between plots
  • the split-screens of the story and the app interface

For the content, I think the story itself worked well because the storyline was straight forward. I showed this video to my friends and they were able to understand what feature I was introducing. Besides the story itself, the background music was also a good match. I received a compliment saying that the music set a relaxed tone and delivered a sense of humor.

In terms of editing skills, I received compliments on the transitions clips I added between plots. I was glad that I asked help from friends who know many filming skills so that I was able to build smooth transitions between plot and plot. In addition, the use of split screens was another effective way to show how the user interacts with the application. In order to avoid the issue that split-screen might keep the screen too busy, I adjusted the transparency of the user interface screen to 75% and placed it on the right top of the screen. With these adjustments, viewers can continue following the story and also view the interfaces that the character was interacting with.

What Needed Improvement

  • narration
  • video resolution

Since the story directly starts with no pre-set themes, without knowing what’s the application at first, the viewers might question the purpose behind each movement. To avoid this issue, I need to add more clear narration.

The video resolution is so bad because the footages were shooted in a dim coffee shop by using a phone. For the future video prototype, I need to consider other factors besides the content itself such as the surrounding environment and the lighting.

Overall, I think my video is effective in demonstrating one basic feature of Lifesum and clearly shows how it can be easily used by people who want to track their daily energy intake. Though, there are still areas needed improvements and could have been more effort into making the story to include more features of the app.

Final Video

The Youtube Link



Michelle (Xin) Gao

UX Research and Design | UW HCDE Alumna | Class of 2021 @ UW MHCI + D