Zero is the all-in-one fasting tracker and nutrition app built for real results. Most fasting and weight loss apps stop at simply tracking fasts or calories. Zero connects the full picture — fasting, protein, meals, hydration, and habits — so you actually change your body composition, not just your eating schedule.
Here’s how Zero helps you get there:
• Track your intermittent fasting — Engage timers, streaks, and insights keep you stay motivated and consistent on your entire fasting journey.
• Log meals the smart way — Skip the tedious manual meal entry routine. Snap a photo and get instant macros, protein composition, and clarity on how effectively your meals support your goals.
• Hit your Protein Score — Track your personalized daily protein target that adapts to your weight and goals. Better protein = better satiety, better muscle retention, better weight loss. Zero makes it automatic.
• Complete the equation: Fasting + Protein — Most people fast or track meals. Zero brings them together so you lose weight, protect muscle, and avoid the pressure and guilt of traditional calorie trackers.
• Stay hydrated to power your fasts — Water tracking helps you maintain energy, reduce cravings, and support metabolic function throughout the day.
• Build healthy habits that actually matter — Track movement, sleep, mood, and other daily pillars that reinforce your fasting and fueling routine.
• Challenge yourself — Hit protein targets, maintain fasting streaks, and stay accountable with motivating challenges built around outcomes, not vanity metrics.
• Learn the real science — Understand how fasting, protein, and hydration work together for sustainable weight loss and metabolic health — with insights from leading experts.
• See measurable progress — Watch your streaks grow, your protein consistency rise, and your body composition improve with clean, insightful trend views.
Whether you’re starting out or optimizing an existing routine, Zero gives you the structure, guidance, and clarity most apps miss.
Zero includes a free version and an optional subscription for premium features. A free trial is available.
Download Zero to get started.
Payment for Zero Plus will be charged to your iTunes Account when you subscribe. Subscriptions automatically renew unless auto-renew is turned off at least 24 hours before the end of the current period. Manage your subscription by going to your Account Settings.
Read more terms & conditions:
Terms of use: https://www.zerolongevity.com/terms-of-use
Privacy policy: https://www.zerolongevity.com/privacy-policy
The app has gotten very buggy. I have observed 2 so far:1. I opened the app and the time delta was negative some huge number, even though the fasting was from 18 to morning next day. Restarting the app didn’t help. 2. When posting mood, I get an infinite spinner.
Developer Response
Hi there – We're sorry to hear you've encountered these two bugs. These are known bugs that our engineers are currently working on. The workaround for issue 1 is to delete the negative number fast and start a new one with an edited start time. We endeavor to have the fix for both issues in the next update for the app which is scheduled to be in the App Store during the first week of January 2023. If you have any questions or would like to provide additional details about what you're encountering please send us an email at support@zerolongevity.com so our support team can assist. – Team Zero
Horrible
Whi Kung Su
Forcing free trial with no way of NOT taking that offer
Developer Response
Hi there - Thanks for reaching out and sorry to hear you’re not able to access our free version. We offer a free trial so that you can access the full scope of the Zero experience, but we’re happy to help if you’re not seeing Zero’s free version. If you’d like help with this or have further questions, please contact our support team at support@zerolongevity.com.. We'll be on the lookout for your message. —Team Zero
Your fasting companion just got even better.
This update brings a completely redesigned Apple Watch experience, deeper fasting insights, and a few quality-of-life improvements throughout the app.
• All-New Apple Watch App: We’ve completely redesigned the Zero Apple Watch experience with a fresh new look and expanded fasting functionality, making it easier than ever to start, end, and track your fast from your wrist.
• More Detailed Fasting Insights: Explore enhanced fasting zones to better understand what your body is doing throughout every stage of your fast.
• Smarter Logging: The logging sheet is now easier to navigate, helping you quickly find the actions you use most.
• Bug Fixes: Improved the weight chart experience when no data is available and fixed a dark mode issue on the MVV screen.
Version 7.12.0
The developer, Zero Longevity Science, Inc., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
Health & Fitness
Location
Contact Info
User Content
Identifiers
Usage Data
Diagnostics
Privacy practices may vary based, for example, on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Provider
Zero Longevity Science, Inc.
Size
249.7 MB
Category
Health & Fitness
Compatibility
Requires iOS 17.0 or later.
iPhone Requires iOS 17.0 or later.
Apple Vision Requires visionOS 1.0 or later.
Apple Watch Requires watchOS 10.0 or later.
Languages
English
Age Rating
16+
16+
This app has an age rating of 16+ with content restrictions.
Some content may be rated higher, and may therefore be restricted and managed by the developer through in-app controls.