Frequently asked questions
Answers to the most common questions about slotho. For anything else, visit the support page or write to us.
Logging food
Where does slotho’s food data come from?
Three places: the public Open Food Facts database, USDA FoodData Central, and a built-in library of over 300 common whole foods that works entirely offline, with names localised into every language the app supports. You can choose the source, sort order and result limits in the food-search settings.
Can I scan barcodes?
Yes — point the camera at a barcode, or pick a photo that contains one. The scanner needs camera permission; if the screen is black, allow the camera under Settings → Apps → slotho.
The product I scanned wasn’t found
You can create it yourself — name, brand, nutrition values and a photo — and log it like any other food. If you choose to contribute the product back to Open Food Facts, it is submitted to their public database so the next person scanning it gets a result. Contributing is optional, and what you submit is the product’s data, not yours.
Does food search work offline?
Searching the online databases needs a connection, but the built-in common-foods library, your favourites and your cached past searches all keep working without one.
What is the keto rating?
Every food whose label declares its macronutrients shows Keto with up to three stars: the smaller the share of its calories that comes from carbohydrate, the more stars. You can even sort search results by it, with Keto-Friendly. The full method is explained in net carbs, and how slotho rates a food for keto.
What are the quality badges on a food?
Nutri-Score (overall nutritional quality), NOVA group (how processed the food is, 1–4), Eco-Score (environmental impact) and the number of additives — shown whenever the database has them.
Fasting
How do fasting schedules work?
You set an eating window for each day of the week by choosing your first meal and your last — different windows per day, or one applied to all days, in Settings › Fasting. Your daily rhythm card shows the window alongside your sleep, and optional notifications remind you when it’s time to start and stop eating. Fasting is a free feature — the fasting page goes through it in full.
What are the fasting stages?
slotho describes six stages as your fast progresses, from Digestion at the start through falling blood sugar, glycogen burning, fat burning, ketosis at around 16 hours and autophagy at around 24. Stage times are approximate and vary from person to person — they’re general education, not medical advice. You can enable a notification as each stage begins; stages you’d sleep through arrive as a morning recap instead. The fasting page lists all six with their onset hours.
Water, caffeine & alcohol
Why did logging a coffee also log water?
That’s intentional. A caffeinated drink logs its caffeine in milligrams plus the liquid volume towards your hydration. Likewise, an alcoholic drink logs standard drinks plus an estimate of its carbohydrates — and the pair is linked, so deleting one removes both.
What is “estimated caffeine remaining”?
An estimate of how much caffeine is still active in your body, using a 5-hour half-life (typical range 3–7 hours). It also shows roughly how much will still be active at your usual bedtime — caffeine late in the day can carry into sleep.
Apple Watch
What can I do on the watch?
The watch opens on today’s water and energy rings and your fast. Swipe down for one-tap logging — drinks, food from your favourites, digestion, mood, fullness and weight — and again for workouts, including your plans, heart-rate zones, indoor or outdoor walks, runs and rides, and switching to another workout mid-session. On watchOS 26 you can log water, a coffee or a bowel movement from Control Centre, the Action button or the Smart Stack without opening the app, and a watch workout shows on your iPhone’s Lock Screen with pause and end. Complications for the watch face are included. The watch app is free; Sloth Pacing and Coach Voice are part of PRO.
Why is there no food search on the watch?
By design — typing and browsing large databases doesn’t suit the wrist. The watch logs from the favourites you’ve starred on the iPhone, so star a few staples first and logging becomes two taps.
Food I logged on the watch isn’t in Apple Health yet
Watch food logs travel through your iPhone. If the phone is out of range the log is queued and delivered when the two next connect — nothing is lost. Drinks, weight, symptoms and workouts are written to Health directly from the watch.
Does my fasting schedule show on the watch?
Yes. Your eating window reaches the watch from your iPhone, the watch face complication shows whether you are eating or fasting, and the watch’s home page names the stage your fast is in.
Apple Health & permissions
What does slotho read and write in Apple Health?
It writes what you log: nutrition, water, caffeine, alcohol, weight, digestive symptoms, workouts and (on iOS 18) mood. It reads those back plus steps, sleep, resting heart rate, activity and your profile basics (age, sex, height) to build charts, goals and insights. You choose exactly what to allow, per type.
Health shows slotho’s read access as “Required” — is that a bug?
No — iOS deliberately hides read-permission status from apps to protect your privacy, so slotho cannot tell what you decided. Check or change what it can read under Settings → Privacy & Security → Health → slotho.
Can I use slotho on iPad?
Yes. iPad has no Apple Health, so anything you log there is held briefly in your private iCloud and written into Health by your iPhone the next time it checks in. Nothing goes to a slotho server — there isn’t one.
Why can’t I delete a History entry?
Apple Health only lets an app delete entries it created itself. Anything logged by the Health app or another app must be deleted in the app that created it.
History, insights & PRO
What’s free and what needs slotho PRO?
Free, forever: unlimited food, drink and symptom logging, the fasting timer with daily schedules, unlimited meal and workout plans, and logging and workouts on Apple Watch. PRO adds the Daily Balance score, Insights (correlations between your meals and your sleep, digestion and energy), sleep-pattern recommendations, the Weekly Recap, your full history beyond the last month, the eating window on the Recap’s rhythm chart, shareable charts, the top-insight widget, and Sloth Pacing and Coach Voice on Apple Watch. PRO also brings its own AI, with no key of your own: meal photos and typed foods read, meal and workout plans drafted, customised voice meditations, and your workout notes voiced, each with a monthly allowance shown in Settings › Intelligence.
Why does my history stop after a month?
The free tier shows your last 31 days. PRO unlocks the rest, loading more in monthly steps. Your data itself is never trimmed — it all stays in Apple Health.
An insight says “insufficient overlap”
Insights compare two measurements on the days you logged both. If they rarely land on the same days, there isn’t enough overlap to say anything honest — keep logging and it resolves itself. slotho also deliberately skips trivially-related pairs (like carbs vs. calories), so every insight it does show is worth reading.
The Daily Balance says “not enough data”
The score combines three factors — food & water, activity, and sleep — and needs data in all three. It shows a provisional “so far today” reading while the day fills in.
My calorie goal looks wrong without an Apple Watch
Without a watch, Health has no measured resting burn. Set Profile → Basal energy budget and slotho uses it as your resting daily burn; measured data always takes precedence when available.
Reminders
What reminders can slotho send?
Fasting start/stop alerts, fasting stage updates, hydration reminders (adaptive — they come sooner when you’re behind your target and stop once you reach it), meal suggestions timed to your eating window, a weekly recap, and a weekly or monthly weigh-in nudge. All of them are off by default.
I’m not getting any reminders
slotho asks for notification permission only when you first switch a reminder on — never at launch. If you declined it then, allow notifications under Settings → Apps → slotho → Notifications and flip the toggle again.
Data & privacy
Does slotho collect my data?
No. There is no slotho account and no sign-in. Your health data lives in Apple Health on your device; meal plans, favourites and settings sync between your devices through your own iCloud. Food-database lookups leave your device, and so does a product you choose to contribute to Open Food Facts. If you use one of PRO’s AI features, the photo, words or choices that feature needs go to a small service red8.io runs on Google Cloud, which keeps only a count against your monthly allowance — never the photo or the words. The Privacy Policy sets out every case.
Is slotho medical advice?
No. Calculations and insights are estimates based on widely recognised guidelines — general information, not a substitute for professional medical advice, diagnosis or treatment.
Purchases, requirements & languages
How do I subscribe, restore or cancel?
slotho PRO is a monthly or yearly subscription; current prices and any free-trial offer are shown on the PRO screen in your local currency. Restore Purchases is on the same screen, and subscriptions are managed or cancelled through your Apple Account like any App Store subscription.
What does slotho require?
iPhone or iPad on iOS 17.6 or later, and watchOS 10.6 or later for the watch app. Mood logging and label translation need iOS 18.
Which languages does slotho speak?
28 languages and regional variants, from Danish to Thai — including the food names in the built-in database. The app follows your device language; to use a different one, go to Settings → Apps → slotho → Language. Food data: © Open Food Facts contributors (ODbL) · U.S. Department of Agriculture, Agricultural Research Service, FoodData Central. Terms & Conditions / Privacy Policy