# Key to Health: Metabolic AI — user reviews > 143 indexed App Store user reviews of Key to Health by Keyto, Inc., rated 4.80/5 from 2,251 ratings. - Source: https://appshunter.io/ios/app/key-to-health-metabolic-ai/id1441365703/reviews - App overview in markdown: https://appshunter.io/ios/app/key-to-health-metabolic-ai/id1441365703.md - Rating breakdown: 5★ 1,890 · 4★ 266 · 3★ 36 · 2★ 17 · 1★ 42 ## What do users think of Key to Health? Overall sentiment: positive **Pros** - 🚀 Easy to use - 👍 Accurate ketone readings - 🚀 Convenient and portable - 👍 Helpful for staying on track with keto - 👍 Motivating and informative app - 🚀 Simple and straightforward **Cons** - 🐛 Connectivity issues - 🐛 Inconsistent readings - 💰 Expensive subscription - 🔍 Limited food database - 🐛 Buggy app updates - 🔍 Lack of customization options **Commonly reported bugs** - App crashes when reaching 100% during measurement - Inconsistent connectivity between device and app - Incorrect weight display in metric units - App stuck in loop during onboarding process **Most requested features** - Add ability to edit or delete recorded readings - Integrate with Apple Health or other fitness apps - Expand food database, especially for non-US users - Provide more personalized coaching and feedback ## Newest reviews (11 of 143) ### 3/5 — Great but… *2026-06-03* This a great little device to measure ketosis. However the app has this fire sound effect after taking measurements that is SO LOUD. I’m trying to take measurements in the beginning of the day upon first waking up, but there’s no way to turn this sound fx off. There is no option to turn it off in the app settings or in apple’s settings. It does not even respond to the volume setting! I should be able to take my measurements without waking other people up. Please allow the option to silence it! ### 3/5 — New Update *2026-03-31, version 4.0.1* The new update doesn’t seem to have been tested. Informational quotes cover the the functional meter when taking a measurement, and the system forces you through and initial questionnaire with no option to skip. ### 3/5 — Great for measuring levels *2024-10-02, version 3.4.1* Another app hawking an overpriced subscription, but the measurement tool works great. I’ve had it for nearly a decade. No complaints on the hardware. ### 2/5 — Beware misleading info and not value for money *2024-09-11, version 3.4.1* I subscribed to the premium version through the App Store as I wanted a free Keyto breath sensor. I checked with the chat AI on the app and all I had to do was subscribe to the premium subscription (nothing else was mentioned). There is only one option for premium when you subscribe through the App Store and that is a monthly payment of £42.99 with a seven day free trial, so I subscribed to the premium just to get the breath sensor to then be told I could not have it free of charge. Even though I had subscribed to premium I had chosen the wrong type of premium subscription. You have to subscribe for the year and pay a monthly rate. This subscription is not an option on the App Store. I contacted the company who explained this to me, but I think you can only see these options from their website. I requested a refund of the subscription (I’m within 7 days of subscribing, so legally entitled to a refund) to be told I had to request this from Apple directly. Not ideal. In addition to this the app is very US focused, there are not many foods to select if you want to log your meals and all the measurements are US e.g. oz. There are not many UK food options at all, if any. In my opinion, it is definitely not worth £42.99/month. The only thing that made it worthwhile is the ‘free’ breath sensor which is currently selling for £77. The company were quick at responding to my questions but obviously I was disappointed with what they had to say. They took no responsibility for the fact that they are misleading people who subscribe to their premium service through the Apple App Store and the responses that their chat AI gave to me. It didn’t mention a specific type of subscription just that I had to subscribe to Premium. ### 2/5 — Never buy a Premium subscription for 2 months. *2024-02-01, version 3.3.10* First- When purchased the app, It was promised with Premium subscription for 2 months that within one week of active participation and learning provided lessons, you get a Keto monitor to measure your ketones. I didn’t get it at all. You will have to buy it separately for 99.99$. Second- The customer service was very bad. It literally took one or two days for them to reply using litter one general sentence and not addressing a particular concerns at all. Unfortunately, customer service was not interested in helping out or explaining details. If it was at least supportive conversation or willing to figure out something or explaining something important to a customer, I wouldn’t write bad review at all, because the app by itself is very informative and very well structured. ### 4/5 — Enjoying the breath sensor. *2023-08-18, version 3.3.10* Despite what some have said I have found it to be generally accurate. It may not always be what I want to hear but it lets me zero in eating for a higher result. Better than strips for sure. ### 2/5 — Disappointing service *2023-02-14, version 3.3.10* Shipping sent via DHL which doesn’t ship where I live. Minimal and unhelpful responses to emails. Without device, app is not worth it. Food tracking is too limited for extended use. ### 5/5 — Fixed issue :) *2023-02-04, version 3.3.10* Accurate sensor and very helpful. I had an issue with the sensor but they were able to resolve it. ### 2/5 — Auto responses. Not real coaching *2023-01-21, version 3.3.10* The coaching is just auto responses when you do certain activities. Nothing really personal here. Their food searches are not nearly as robust as other (free!) apps. Not worth the $50 a month. Not clear how to contact customer service for help, my Keyto device has been lost in shipping. ### 5/5 — Keyto Rocks! *2022-08-28* Joined 2 years ago, Love Love Love my breathalizer and the app. Only using it 3-4 times a year now, especially after holidays…. To check-up get back on track. It works Best purchase :) Annie ### 5/5 — Keyto Breath analyst *2022-08-24, version 3.3.10* It takes all the guess work out of …. If I eat this will I still be in Ketosis. I now know what helps and hurts my Keto depths, which keep me on track ! Valuable information to help reach your goals ! Highly recommend Keyto analyzer ! ## Most critical reviews (10 lowest-rated) ### 1/5 — Don’t Bother *2026-05-25, version 4.0.3* This is a scam…I can no longer use my Keyto because they decided to charge $50 a month to use the app. This was free. ### 1/5 — Useless to me since last update *2026-03-31, version 4.0.1* I’ve used the sensor for about a year, and kept a 30 day average of 4-4.8. Since the update, I get a continual battery low indicator (even after 3 battery changes), and mostly get readings of 1. Very annoying that I couldn’t even take a reading after the update without 10 minutes of questions by an AI tool that seems untrained. I’m giving up. It offers no value. ### 1/5 — Keyto data doesn’t since with Apple health *2025-11-19, version 3.4.1* Hands down the worst health data app ever made. Write my keyto score to the health app. Or at least allow me to download my data. Seriously, it’s 2025. Give me my data ### 1/5 — "Generous" 3 months manufacturer warranty! *2025-01-31, version 3.4.1* The device worked well at first, but my Keyto stopped functioning just four months after purchase. I was disappointed to learn that the warranty only lasts three months, which seems questionable. Too many devices stop working past 3 months of use? Unfortunately, this ended up being a waste of money. Given there are no negative reviews on their website is telling as well. ### 1/5 — Will stop working right away *2024-08-16, version 3.4.1* I’ve used this device maybe 10-15x and now it never works. I uninstalled and reinstalled the app, made sure the battery was replaced with a new one. It takes FOREVER to warm up, and will get to the end and fail. I’m talking 3-4 mins of warm up just to have it fail and you have to start over. It wasn’t terribly annoying when I had to do it 1-2x before I could blow into it. Now I can do it 5x in a row and it never connects. Total waste of money. I should have spent more and gotten a lumen. ### 1/5 — Unreliable *2024-06-02, version 3.4.1* Device bricked itself without cause after a couple of years, app rendered useless. ### 1/5 — Don’t scan uk bar codes *2023-12-20, version 3.3.10* Don’t scan uk bar codes everything is USA USA friendly it’s definitely not uk friendly and the price is expensive and if you ask for a refund they says can have one but still send out the device so I don’t think I will get my refund ### 1/5 — Device v App *2023-03-25, version 3.3.10* I love the device, it is really making a difference for me to be able to see my Ketone levels. The app is OK. It shows you the level your device is reading and coaches you on when to breathe.. As far as tracking food intake, I prefer Carb Manager, which unfortunately, only interfaces with a different keto breath analyzer ### 1/5 — Can’t use the breathalyzer without $50/mo membership *2023-03-18* As others have said, the dietary tracking lists are minimal and cumbersome to use. “Coaching” is canned messages pushed out in response to some activity in the app. I haven’t received a “coaching” message since the day I stopped recording in the app few weeks ago - I’d have expected some sort of encouragement to continue. There’s no way to contact anyone for coaching support within the app and you can’t reply to the messages you receive. I’d pay something other than $50 to be able to keep using the breathalyzer without the other aspects of the app, but there’s no option for that. $100 breathalyzer and $50 1 month membership down the drain. ### 1/5 — Unusable *2022-08-23, version 3.3.10* The app requires you to create an account with them.. which is annoying but I normally wouldn’t complain. However, their website’s API is broken which renders the signup process an impossibility, with no fallback option to use the device you paid for. The old app was absolutely amazing. No need to fix what isn’t broken. ## Most praised reviews (10 highest-rated) ### 5/5 — Great device and app *2026-07-09, version 4.0.3* Really love this device and app. I wish you’d make a change to the age ratings. It’s on 18+ now so I cannot use it on my phone. Don’t see why this needs to be 18+. Even 16+ would be very conservative. ### 5/5 — New design is magic *2026-05-30, version 4.0.3* I have been using Keyto on and off for many years with great results. The new design is super. It was a much needed refresh and it delivers. Excellent product. ### 5/5 — Trends *2026-04-17, version 4.0.1* I don’t have a subscription, so maybe that is why every single day it shows that I it is my first time blowing. It doesn’t show my trend. ### 5/5 — Easy to use, reliable *2025-11-30, version 3.4.1* Only short coming is the inability to add or edit notes after a reading is recorded in Journey. Also tedious to drill down to see the individual days. The only option at that level in the app is “ cancel “ or “delete”. There needs to be another option, “edit note”. Thanks. ### 5/5 — Keyto Rocks! *2025-01-13, version 3.4.1* Love Love Love my breathalizer and the app. Only using it 3-4 times a year now, especially after holidays…. To check-up get back on track. It works Best purchase :) Annie ### 5/5 — The key to keto is Keyto *2024-11-17, version 3.4.1* Great app very easy to use and with the ketone breath meter every just works. Very well setup to ensure you succeed. Love this app. ### 5/5 — Couldn’t be happier with Keyto meter *2024-05-15, version 3.4.1* I’ve had the Keyto for several years and it works flawlessly every time. It’s helped me stay on track and motivated. Highly recommend! ### 5/5 — Learning Curve *2023-09-01, version 3.3.10* Learning how to achieve proper macro balance with healthy, sustainable food choices takes focus and effort. However…figuring this out for yourself is key to ongoing success. Down 43lbs. ### 5/5 — iPhone 13 pro max *2023-04-29, version 3.3.10* This is high one of the rarest lowest cost point consistent and accurate device I recommend. I have several devices to double check its calibration and it’s always consistent. Do yourself a favor support this company. Dr. MA ### 5/5 — Keyto is Neato *2023-03-09, version 3.3.10* Simple to use, straight forward info for Low Carb lifestyle combined with the Keyto breath device. The graphics are simple and navigation a breeze. The coaching segments add fun to the keto process. I love this device! --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-29.*