Allowing people to leave helpful product reviews

Product reviews for mobile and desktop

Summary: Mercado Libre, the biggest e-commerce site in Latin America, needed a way for their customers to leave product reviews using the mobile app (iOS, Android and web).

My role: For this project, I was in charge of leading the initiative: designing the concept, testing it with users, co-designing the UI, and supporting the implementation.

The problem to solve

Mercado Libre sells hundreds of millions of products each year and more than 50% of their users come from mobile devices. However, we didn't have a way for them to leave a review using their mobile app. We were missing a big opportunity to help potential buyers decide on a product. To solve this problem, I worked along with a team of engineers and a PM.


  • The first challenge was conversion. Are people willing to write product reviews in their mobile devices? Are they willing to write product reviews at all? People read reviews, but writing them is a different story.
  • The second challenge was a very tight deadline to launch the first version of the solution. Prioritization, clear communication and team work were essential in order to succeed.
  • The third challenge is a little more complex. Users in ML buy from other users or companies. Initially, they were allowed to leave feedback related to their experience with the sellers (good or bad), but not necessarily about the product.

A first attempt to enable product reviews was made, having as a result product reviews like “The seller was great! The product arrived right on time!”. As you can see, we need to understand the users mental model and how we can start shifting the idea of reviewing the product and not the experience (since we already know when the purchase is completed and if the product is received by the users).

The solution

To tackle the first two challenges, we allowed users to write product reviews in their mobile application (iOS, Android and web). I was in charge of designing the concept, test it with users, and co-design the UI.

And in order to tackle a -basic- first stage within the third challenge, we used some tricks to identify if the user is talking about the product or the seller, if the review is too short, etc.

The process

To start, I ran a quick competitive analysis to see how others were doing it. Then sketches to visualize the idea with the team and stakeholders.

Rough sketches I made to help the team visualize the idea.


Screen Shot 2017-03-01 at 22.04.10
Low-fidelity explorations


Once we agreed on the direction, different variations of a design were tested with users in order to identify problems and opportunities. As the moderator, I allocated time from every session to ask more contextual questions in order to inquire about what they do after buying and using a product—if they leave reviews, what are the biggest pain points when doing so, etc. I invited the project leader to join me during the sessions.

While adjusting the designs based on user feedback and designing for edge cases, we started -along with a visual designer-exploring visual solutions, illustrations, and animations to make sure we were telling the right story in a compelling way. I also introduced the content strategist to the team, in order to bring the voice of ML into this solution. Usually, I start with a rough idea of what I want to communicate and then we work together to improve it. As a technical leader, I am generally in charge of orchestrating the communication and work between the UX team (partly remote) together with the IT team and PMs.

Visual exploration

iOS 375x667
Mobile flow

FAE extendido
Making the most out of the product reviews right on the product page

Comentario lleno
Redesigning the process of writing a product review using staged disclosure

Motion design, from ideas to implementation:


Screen Shot 2017-03-01 at 21.23.35
Animation guide for developers


Content strategy

Screen Shot 2017-03-01 at 21.18.04
Collaborative content document

At the same time, the dev team started coding the structure for this flow since they were involved from the beginning and were aware of the idea. During the implementation of the application, we needed to quickly adjust some details, but nothing major. Generally, I'm also involved in the testing stage, assuring we are delivering with quality.


  • Almost 80% conversion (people who started the process and concluded leaving a product review) using our solution.
  • Less product reviews talking about the purchase experience and more about the product itself. Still relatively short reviews though.
  • Metrics in place, a deeper understanding and new ideas to tackle next challenges.