Review Insights · App Store
Zero: Fasting & Food Tracker
Zero Longevity Science, Inc. · 445,256 ratings · ★ 4.8
4.8
★★★★★
445,256 ratings
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Top complaints - extracted from 76 negative reviews
Recurring phrases mined from 1-2★ reviews. The bigger the percentage, the more users have the same problem. Fix the top 2-3 in your version and you have product-market fit on day one.
1
"free"
18 negative reviews mention this · 24% of all complaints
★★★★★ "Terrible. I want to use the free features but it won’t let me unless I sign up for a free trial. Not trust worthy. Scam." - Jrg369
2
"fast"
16 negative reviews mention this · 21% of all complaints
★★★★★ "Idiotic. Congratulations on building a bare bones app, which provides zero information, motivation or guidance during a fasting state. What are you asking $$ for? So I can tell you the start and end day of my fast? Lol, what a joke" - 8Sunny8
3
"update"
13 negative reviews mention this · 17% of all complaints
★★★★★ "Cost. I had the old version of this app for years and went to update my phone and redownloaded it only to find out I now have to pay for it. I don’t want all the fancy stuff they charge for now and it sucks you can’t even use it anymore with out …" - Kaceyyyyuuhhyyy
4
"years"
12 negative reviews mention this · 16% of all complaints
★★★★★ "Cost. I had the old version of this app for years and went to update my phone and redownloaded it only to find out I now have to pay for it. I don’t want all the fancy stuff they charge for now and it sucks you can’t even use it anymore with out …" - Kaceyyyyuuhhyyy
5
"subscription"
12 negative reviews mention this · 16% of all complaints
★★★★★ "Cost. I had the old version of this app for years and went to update my phone and redownloaded it only to find out I now have to pay for it. I don’t want all the fancy stuff they charge for now and it sucks you can’t even use it anymore with out …" - Kaceyyyyuuhhyyy
6
"sign"
10 negative reviews mention this · 13% of all complaints
★★★★★ "Terrible. I want to use the free features but it won’t let me unless I sign up for a free trial. Not trust worthy. Scam." - Jrg369
7
"trial"
9 negative reviews mention this · 12% of all complaints
★★★★★ "Terrible. I want to use the free features but it won’t let me unless I sign up for a free trial. Not trust worthy. Scam." - Jrg369
8
"paid"
9 negative reviews mention this · 12% of all complaints
★★★★★ "Not worth it. It’s a paid app" - Sophia Boxton
9
"working"
9 negative reviews mention this · 12% of all complaints
★★★★★ "Watch app not working. I have paid subscription but why is the app on my Apple Watch not working… please fix" - Hihi.april
10
"without"
9 negative reviews mention this · 12% of all complaints
★★★★★ "Used to be good. Impossible to sign in without giving all your details and even if you do put details in it’s a 50/50 shot it will work." - Bummer j
11
"password"
9 negative reviews mention this · 12% of all complaints
★★★★★ "Update broke it. Can't log in. Can't even reset a password. Can't anything. Removed the app because it's not useable at all after that update" - KristynRene
12
"fasting"
8 negative reviews mention this · 11% of all complaints
★★★★★ "Idiotic. Congratulations on building a bare bones app, which provides zero information, motivation or guidance during a fasting state. What are you asking $$ for? So I can tell you the start and end day of my fast? Lol, what a joke" - 8Sunny8
📋 All 76 negative reviews
Every 1-2★ review we fetched. Use the copy button to grab them all for your own analysis (paste into ChatGPT/Claude with a prompt like "summarize core user problems, group by theme, ignore bugs, focus on missing features").
Terrible
I want to use the free features but it won’t let me unless I sign up for a free trial. Not trust worthy. Scam.
Cost
I had the old version of this app for years and went to update my phone and redownloaded it only to find out I now have to pay for it. I don’t want all the fancy stuff they charge for now and it sucks you can’t even use it anymore with out a subscription
Idiotic
Congratulations on building a bare bones app, which provides zero information, motivation or guidance during a fasting state. What are you asking $$ for? So I can tell you the start and end day of my fast? Lol, what a joke
Not worth it
It’s a paid app
Widget does not work
Widget continues to count your fasting timer even after you end the fast. Haven’t fixed for months. App now completely useless.
Was Free, Now Expensive
I used to love this app. I had stopped using it for a while to start 2026 as the year has been pretty crazy. Finally was in a spot where I am ready to get back into fasting and opened the app to find out you HAVE to pay to use it now.
Disgusting. Any app that claims to care about health and then charges $70 to use it is lying about caring about your health. Only cares about your money.
I noticed they added that AI calorie counter thing where it guesses the calories based off a picture, and I bet that’s why it s so expensive now, because AI is expensive. News flash, NOBODY WANTS THAT BS!!!
Disgusting. Any app that claims to care about health and then charges $70 to use it is lying about caring about your health. Only cares about your money.
I noticed they added that AI calorie counter thing where it guesses the calories based off a picture, and I bet that’s why it s so expensive now, because AI is expensive. News flash, NOBODY WANTS THAT BS!!!
Not free and such a long sign up process.
Don’t waste your time it wasted 9 min on my day when I easily downloaded fast yin 30 seconds hopefully they don’t delete this review. 0 stars.
Watch app not working
I have paid subscription but why is the app on my Apple Watch not working… please fix
Used to be good
Impossible to sign in without giving all your details and even if you do put details in it’s a 50/50 shot it will work.
Can’t use a free version?
Since when does it force you to do a trial or pay for a subscription
They broke the app and paywalled it
What a joke. Undo the latest update and return to your old model.
Worst app
Auto charges even when you cancel
No longer free
I loved using this app to track a fast. With a $70 annual fee, I will now delete the app.
Pay to use
You HAVE to buy a subscription to use the app.
Unable to connect to account
I have a year paid subscription to Zero. After being logged out, I logged back in using my Apple ID credentials and the app no longer shows my subscription. I’ve tried logging in every different way the app provides and none link to my subscription.
Why ??
I’ve been using the app for almost 5 years. I was so proud to see the numbers of days I fasted climb and climb. But your latest update zeroed my fasts out. I’m so disappointed :(
New update is unusable
I have used Zero for years but this new update completely ruined the app. Not only is there UI issues making accessing old data incredibly difficult but the app is simply a paid app at this point. There are no free features. A great app ruined by its creators greed. Will delete and it’s a total shame.
How the HECK did i get banned?
All of the sudden it logs me out and next page i see “Your not a good candidate” WTH??
What the …..!
Is not working now!!! Haven’t had any issues this
Week
Now
It won’t let me
Do
Anything
Week
Now
It won’t let me
Do
Anything
Update broke it
Can't log in. Can't even reset a password. Can't anything. Removed the app because it's not useable at all after that update
The stupid thing shut down
It was working fine and then it all shut down and won’t let me login. I hate this. I’m deleting it.
Do not like the update
The latest update logged me out and I can log back in. The link for resetting the password doesn’t work. Why can’t you just leave it alone? Now I have to cancel the app
App Not Working
The app was working for me two hours ago and now every time I try to login in is just loads and doesn’t do anything.
I turned my phone off and on.
Deleted the app and redownloaded it.
Nothing is working
I turned my phone off and on.
Deleted the app and redownloaded it.
Nothing is working
Great Until it Wasn’t
The app was great, then it logged me out and won’t let me log back in, so I had to delete the app and cancel my subscription. I tried everything, resetting my iPhone, deleting and reinstalling the app. All to no avail. It was good while it lasted.
Random logged out
Randomly logged me out of my account in the middle of a fast and now won’t let me back in.
Update broke the app again.
Update forced a sign out, now can’t sign back in.
It’s garbage!
Let me preface this by saying that (I’m on the free app) I’ve been using this app for quite a few years and recommended it to others. Going back over a year, the app started deleting my fasting timer so I was totally lost as to where I was on the fast. I started keeping notes just to make sure on the times. It has been logging me off without notice and at times I can’t log back in. I troubleshooted today for over an hour and I’m done ✅ I’m tired of the persistent “unpredictability” of this touchy app (deliberate, I’m sure) and of the pop-ups and ads, creating more steps to see my timer. Zero you get if I had a choice!
App doesn’t work
Just canceled my subscription. The app locked me out and makes errors when I try to reset the password. Too bad! There are other fasting apps.
Logging in issues since their update
Zero is unreliable now. I’ve had this account since 2022 and previously paid for a subscription, then returned to the free version. Now the app forces a login even for free use and shows Facebook login errors even when I’m signing in with Apple ID. I deleted and reinstalled the app twice, and it still does not work. Other users are reporting the same issue, yet Zero is not being upfront or honest with customers about what’s going on. At this point, it’s time to decommission this app.
App pushes the subscription every. Single. Time.
Ruined the app yet again. Can’t log in anymore, can’t reset my password and every way to log in is broken. Whatever “fixes” they made didn’t do anything but lock me out of the app. Great to not know when my fast ends now.
Can’t login after update
Can’t login after update
App Problem
It logged me out and cannot get back in.
Not working
I downloaded the app now is not working or letting me login in
Quite buggy
I am a paid subscriber, the app has currently locked me out with no access and no way to even reset the password. Password reset page shows some Google api key error. No way to get live support either, have sent an email and hoping something will happen. Very poor user experience. Will switch when I can take my data elsewhere
Can’t login or reset password
Updated my phone to the latest OS, uninstalled and reinstalled the app, turned phone on and off, tried to reset my password and get hit with a bunch of errors, nothing works. App is not letting me login.
Not Working After Update 4.11.26
Worked fine for years but can’t log in anymore. Tried deleting app, resetting password-nothing worked
New update broke log in
Been using this app for years. Now it logged me out and cannot get back in
App doesn’t work
This app is not currently working
Can’t Log In?
Nice to know that the app I’ve been using for months now won’t let me log in. 🤦🏻♂️
Errrorrrr
I tried logging and then reset my password... now its giving an API error! I just started paying for the app! Please fix this backend error!
Apple Watch widget broken
Decent app gets the job done. Are y’all aware that your Apple Watch widget has been broken for at least a week? Pretty worthless at the moment.
Bait and switch
Says free version is available but requires you to sign up for the premium plan or trial before you get to use any features. No way to click off the screen to access just basic content without signing up
Apple Watch tracker doesn’t work anymore
The Apple Watch fast complication no longer works after updating to 26.4 on all devices. New iPhone and watch.
Formerly good, now trash
The pop-ups and ads just got worse and worse. Now it’s actually unusable if you don’t pay, which I think is a shame. Sorry nobody wanted to read your fake articles or pay monthly for your bells and whistles. If it was a one-time cost for an ad-free, simple timer, I’d be all in. But tech bros gonna tech bro I guess.
extremely disappointed
I’m very sad to be typing this because I’ve been a Zero user since 2020. But they updated the app and now it’s forcing us to pay for a membership in order to use the app. Not everyone can afford to throw money into an app just to track how long our fast is… I understand limiting certain features in order to encourage people to pay for their membership but this is on another level. please fix this issue, I really liked this app and now I won’t even be able to use it.
not free/do not download
just wanted a timer, like some other people in the reviews. don’t know why i didn’t read the reviews first but yea inescapable pop up add after they grab all your info - don’t waste your time on this app
They overcharged when you purchased the app
Too pushy
Limited food entries
Hit my phone in error and stopped my fast so now numbers are incorrect. I
Am not going to go for the subscription. The app is too difficult to use and makes up
Data for food entries by photo. Booo
Am not going to go for the subscription. The app is too difficult to use and makes up
Data for food entries by photo. Booo
Totally revamped to be a diet!
This app was initially marginally useful enough to pay for. You could track how long you fast overnight and together with sleep, movement and mindfulness you built your pillars of health. Now it wants you to track your food and it has turned into a poorly designed dieting app! Waste of money and I’m annoyed that it is no longer what I paid for.
Not free👍🏻
They make sure to have you create a profile and collect all your info before taking you to a screen to sign up for a monthly plan that you can’t click out of.
+ 26 more in the clipboard copy
Sentiment summary
96%
Positive (4-5★)
2%
Neutral (3★)
2%
Negative (1-2★)