Zero — Fasting Tracker
Zero is the world’s most popular app for intermittent fasting. It assists users in fasting safely and successfully, based on cutting-edge physiological research.
We ran several Design Sprints with Zero's product team at Big Sky Health, followed by additional product design work, and helped evolve the initial MVP into a sophisticated product for a growing user base.
YEAR
2018 - 2019
ROLE
Product Design Director
TEAM
Britta Diem, Dee Scarano, Rob Hamblen, Jonas Schmahl, Fedor Shkliarau, Michael Smart
The Challenge
When we started working on Zero, it was an effective, but simple time tracker for intermittent fasting. In our initial research we interviewed fasting experts, Zero's team, and users, and identified several challenges that needed to be solved.
Guidance
Especially beginners were unsure how to start, and Zero's MVP didn’t ease them into fasting successfully. And since not every approach to fasting is suitable for everyone, they struggled and gave up quickly.
For example, users weren't guided on how to properly begin and exit a fast, even though the subjective fasting experience depends a lot on the last meal before the fast starts, and the meal that ends it.
Additionally, Zero's first version only offered two types of fasting, and didn’t help experienced users to progress to longer fasting types that offer more health benefits.
Education
Another area of improvement was how Zero bundled its resources on the science behind fasting. Although Zero's team worked closely with scientific advisors and had access to cutting-edge research, the content was unorganized and users found it difficult to find what they were looking for.
This left inexperienced users vulnerable to misinformation, as a lot of content about fasting on the internet is either false, outdated, or misleading. Providing reliable information for a lay audience was an opportunity for Zero's new version!
Workshopping with Zero's CEO and product team.
Generating and sketching ideas
Approach
Over the course of several Design Sprints, we rebuilt the entire user experience from the ground up, keeping the fasting timer as Zero's centerpiece. We simplified the UI and added visual cues to make fasting progress easier to track. We also created a scalable system to offer new fasting types and allow users to create personal fasting programs.
The reason I chose Design Sprints as a methodology for Zero was that the product really needed to evolve. It was crucial for speed, and for not getting into analysis paralysis that you'd typically get in your normal building cycle. The process is so efficient and well worked out that this was a natural way for me to take Zero to the next place.
— Mike Maser, CEO of Big Sky Health and Zero
Zero's new fasting screens
Comprehensive statistics, integrated with HealthKit, provide users with an overview of their progress and fasting history, along with rewards for fasting streaks.
A new, improved knowledge base gives users access to reliable, high-quality fasting content vetted by Zero's Chief Medical Advisor, Peter Attia.
In addition to this, a premium coaching program helps new users build a routine, and guides experienced fasters toward longer fasting types.
Several ways in which Zero provides guidance to users
We validated each of the improvements and new features in several rounds of user tests. We tested with existing Zero users, experienced fasters that never used Zero before, and complete beginners to fasting.
The feedback from users allowed us to iterate rapidly on each feature, refining what worked, and revising what missed the mark.
This enabled Zero's product team to implement highly detailed and proven feature concepts after the Sprints had ended. This increased focus and alignment, but also saved time and resources, and reduced the risk of technical debt.
Zero's new profile view and knowledge base
Results
Through Design Sprints and our product design expertise, we helped evolve Zero from a simple MVP into the world's most popular app for intermittent fasting.
Today, over 600,000 people use Zero to fast at any given time. It's the easiest way to fast safely, build a routine, and experiment with longer fasts. Users love Zero. This is reflected in the incredible 4.9 out of 5 rating on Apple's App Store, based on over 200,000 reviews.
Although the core Zero experience remains free, our work also helped to define and validate premium features to allow Big Sky Health to monetize Zero. This ensures the sustainability of the product, while also offering optional tools for power users that want to level up their fasting.
Selected Works
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