Zero: Fasting & Food Tracker

Name: Zero: Fasting & Food Tracker
Rating: 4.8 (445059 reviews)
Author: Zero Longevity Science, Inc.

Intermittent Fasting Timer

Free · In‑App Purchases

445K Ratings
Ages

16+
In-App Controls
Category

Health & Fitness
Developer

Zero Longevity Science, Inc.
Language

EN
English
Size

226.8
MB

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

Events

MAJOR UPDATE

Protein-Powered Fasting

Zero now harnesses AI for intelligent meal and protein tracking. Zero is your ultimate fasting and fueling partner.

Ratings & Reviews

4.8

out of 5

445K Ratings

Works. 30lbs in 2.5 months
04/30/2022

reviewer0102030405
I tried keto, I tried them all. Ended up binging and gaining more back quickly. Found fasting and really knocked out the cravings. With Zero it’s really easy to follow your progress without feeling like you’re staring at a clock waiting to eat again. The articles help ease your mind in the beginning knowing that your hunger pangs and other side effects are common and have reasons. Also how to avoid them and get past the fasting wall. I love the timer and how you can count up or down. I count up because I like seeing how far I can push myself within reason. Counting down makes me want to eat as soon as it hits 0:00. The app has some great tracking features and syncs up with apple health so it takes down the data from my smart scale. Nice knowing that I don’t have to manually enter everything every time. A welcomed improvement would be a way to change the theme of the app to keep it fresh or personalized. Different colors etc. this is a small ask for me. Overall I love the app and have lost 30lbs, 6%body fat in 2.5 months. Tbh I haven’t exercised much at all. Just having my body do what it does and use the energy I’ve stored away for years. But now losing the weight of nearly two full size dyson vacuums, I have more energy both mentally and physically that I now crave to get out and do more
Works. 30lbs in 2.5 months
04/30/2022

reviewer0102030405

I tried keto, I tried them all. Ended up binging and gaining more back quickly. Found fasting and really knocked out the cravings. With Zero it’s really easy to follow your progress without feeling like you’re staring at a clock waiting to eat again. The articles help ease your mind in the beginning knowing that your hunger pangs and other side effects are common and have reasons. Also how to avoid them and get past the fasting wall. I love the timer and how you can count up or down. I count up because I like seeing how far I can push myself within reason. Counting down makes me want to eat as soon as it hits 0:00. The app has some great tracking features and syncs up with apple health so it takes down the data from my smart scale. Nice knowing that I don’t have to manually enter everything every time. A welcomed improvement would be a way to change the theme of the app to keep it fresh or personalized. Different colors etc. this is a small ask for me. Overall I love the app and have lost 30lbs, 6%body fat in 2.5 months. Tbh I haven’t exercised much at all. Just having my body do what it does and use the energy I’ve stored away for years. But now losing the weight of nearly two full size dyson vacuums, I have more energy both mentally and physically that I now crave to get out and do more
Updated: Room for Improvement
11/21/2023

Mattiekinsss
21 Nov Update: The developers reached out to me from my initial review and were super helpful and were able to walk me through how to better navigate the app. My lack of understanding how to fully use all the features is why I struggled to change fast settings without saving it as a preset. Due to their amazing response, explanations and helping me fix my complaints deserves 5 stars. It’s definitely worth the subscription and has earned 5 stars in my book.👌🏾 I can recommend this app 100% ⭐️⭐️⭐️⭐️⭐️—————————————————————It’s ok, I love the majority of the features. & unfortunately I forgot to cancel after my free trial. But it’s not worth $70/year. I don’t understand why there isn’t an option to shift or plug in a fast without having to make it a preset. Life happens and I sometimes do an odd hour fast just to get back on track. But that doesn’t mean I want it to be saved as a preset. You should have the option to just put in a fast without being forced to save it as a template. They’re typically one off fasts. The lack of flexibility there is annoying. It’s also odd that it’s not an option under the premium section. If I’m paying to track my fasts it should be a bit more flexible for the price we’re paying. I’ll look for another app that has this simple feature. It’s great aside from that.

Developer Response
Hi there – Thanks for takiing the time to provide this feedback. If you'd like a refund please visit the following link and choose 'Billing & Subscriptions' then 'Request a Refund": https://getsupport.apple.com/productsGood news! There's no need to make it a preset. If you'd like to fast longer than your goal, go ahead and when you've reached your desired duration, tap the end button on the timer. If you'd like to set a shorter goal (1) tap the small number in the circle just above the timer and to the right (2) tap 'Custom Fast' (instead of tapping a space under 'Your Presets') (3) choose the duration (4) tap 'Load Fast' (if not in a fast already) or 'Change Fast'(instead of 'Save As Preset') if no fast is running on the timer. If you'd like help with these items or anything else in the app please email us at support@zerolongevity.com with the details and include reference #68995 and our support team will assist you directly. –Team Zero
Updated: Room for Improvement
11/21/2023

Mattiekinsss

21 Nov Update: The developers reached out to me from my initial review and were super helpful and were able to walk me through how to better navigate the app. My lack of understanding how to fully use all the features is why I struggled to change fast settings without saving it as a preset. Due to their amazing response, explanations and helping me fix my complaints deserves 5 stars. It’s definitely worth the subscription and has earned 5 stars in my book.👌🏾 I can recommend this app 100% ⭐️⭐️⭐️⭐️⭐️—————————————————————It’s ok, I love the majority of the features. & unfortunately I forgot to cancel after my free trial. But it’s not worth $70/year. I don’t understand why there isn’t an option to shift or plug in a fast without having to make it a preset. Life happens and I sometimes do an odd hour fast just to get back on track. But that doesn’t mean I want it to be saved as a preset. You should have the option to just put in a fast without being forced to save it as a template. They’re typically one off fasts. The lack of flexibility there is annoying. It’s also odd that it’s not an option under the premium section. If I’m paying to track my fasts it should be a bit more flexible for the price we’re paying. I’ll look for another app that has this simple feature. It’s great aside from that.
Developer Response 11/20/2023
Hi there – Thanks for takiing the time to provide this feedback. If you'd like a refund please visit the following link and choose 'Billing & Subscriptions' then 'Request a Refund": https://getsupport.apple.com/productsGood news! There's no need to make it a preset. If you'd like to fast longer than your goal, go ahead and when you've reached your desired duration, tap the end button on the timer. If you'd like to set a shorter goal (1) tap the small number in the circle just above the timer and to the right (2) tap 'Custom Fast' (instead of tapping a space under 'Your Presets') (3) choose the duration (4) tap 'Load Fast' (if not in a fast already) or 'Change Fast'(instead of 'Save As Preset') if no fast is running on the timer. If you'd like help with these items or anything else in the app please email us at support@zerolongevity.com with the details and include reference #68995 and our support team will assist you directly. –Team Zero
Literally life changing!
08/08/2021

Msatx
This app has been literally life changing! I accidentally stumbled upon it, just wanted something SIMPLE to log my fasting hours when I first started learning about intermittent fasting but it has sparked my interest in all things related to fasting and health. Im not able to afford paid version and Im extremely grateful that the free version has enough basic information and tracking features to inspire change and at least plant that seed to help people want to learn more, and to want to live with more insight, regardless of economic situation. I was that moron.. the one watching with suspicion while wolfing down pizzas, thought people fasting were just weird food hating extremists. This app has been a revelation, and has been instrumental in opening the door to a new world to me so to speak. It has been invaluable in changing my attitude towards food, fasting, meditation. If you have the means to buy the paid version do it, it will be a small investment for what you get. For me sadly the the price point for the paid version for this and the podcast is not doable but the free version can be very eye opening. Dont just log fasts like I did at first. Dive in and discover everything on the app thats available for free and listen to the podcasts. Fasting and tracking my glucose is now my normal way of life. Grateful.
Literally life changing!
08/08/2021

Msatx

This app has been literally life changing! I accidentally stumbled upon it, just wanted something SIMPLE to log my fasting hours when I first started learning about intermittent fasting but it has sparked my interest in all things related to fasting and health. Im not able to afford paid version and Im extremely grateful that the free version has enough basic information and tracking features to inspire change and at least plant that seed to help people want to learn more, and to want to live with more insight, regardless of economic situation. I was that moron.. the one watching with suspicion while wolfing down pizzas, thought people fasting were just weird food hating extremists. This app has been a revelation, and has been instrumental in opening the door to a new world to me so to speak. It has been invaluable in changing my attitude towards food, fasting, meditation. If you have the means to buy the paid version do it, it will be a small investment for what you get. For me sadly the the price point for the paid version for this and the podcast is not doable but the free version can be very eye opening. Dont just log fasts like I did at first. Dive in and discover everything on the app thats available for free and listen to the podcasts. Fasting and tracking my glucose is now my normal way of life. Grateful.
App forcing me to pay for premium
07/27/2023

Miaosore
I loved this app and found myself using it for over a month. The mechanics are simple and it’s a great way for me to keep track of my fasting! However, recently it began trying to force me to subscribe to premium. Every time I open the app, a pop up comes onto the screen and tries to force me to subscribe to premium. There is no way to get off this screen and access my fasting timer again unless I actually subscribe to the premium feature. Whether I update the app or restart it, it stays stuck on this subscription page. It’s very frustrating that now, an app that was meant to be free with optional paid features, is forcing me to pay to access features that were previously free for me. I really want to continue using the app but I’m so frustrated that I’m considering deleting it.Update: the app just sent me a notification claiming my access was “unlocked” for me to use the app for free again without premium. Once I opened the app the pop up appeared again but this time with an “x” on the top right corner. While I will give this app an extra star because the problem is fixed, I still don’t find it fully enjoyable to use an app that temporarily forces you to pay them despite marketing themselves as a free app with “in-app purchases” which are optional.
App forcing me to pay for premium
07/27/2023

Miaosore

I loved this app and found myself using it for over a month. The mechanics are simple and it’s a great way for me to keep track of my fasting! However, recently it began trying to force me to subscribe to premium. Every time I open the app, a pop up comes onto the screen and tries to force me to subscribe to premium. There is no way to get off this screen and access my fasting timer again unless I actually subscribe to the premium feature. Whether I update the app or restart it, it stays stuck on this subscription page. It’s very frustrating that now, an app that was meant to be free with optional paid features, is forcing me to pay to access features that were previously free for me. I really want to continue using the app but I’m so frustrated that I’m considering deleting it.Update: the app just sent me a notification claiming my access was “unlocked” for me to use the app for free again without premium. Once I opened the app the pop up appeared again but this time with an “x” on the top right corner. While I will give this app an extra star because the problem is fixed, I still don’t find it fully enjoyable to use an app that temporarily forces you to pay them despite marketing themselves as a free app with “in-app purchases” which are optional.

Zero just got a whole lot stronger — and we’re excited for you to try it! Most people don’t get enough protein — and that gap only widens when you’re fasting. Yet maintaining and building muscle is one of the key drivers of optimal health at any age. This release adds the feature we’ve always wanted to bring you: a personalized Protein Score that makes it easy to hit your daily target. Just snap a photo of your meal and Zero uses advanced AI to estimate your protein, assess meal composition, and give insightful guidance on how to adjust to hit your target and achieve real results. Combined with our award-winning fasting tools trusted by millions, with an all-new hydration tracking feature, and refined habit tools, this is the most complete version of Zero we’ve ever built.

Version 7.0.0

8h ago

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