Comparison

Spark vs slotho

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Spark

This offline calorie tracker helps you monitor your daily food intake and body measurements. It features a built-in Russian food database and allows for custom food entries. Sync your progress with Apple Health for a comprehensive overview of your health journey.

Highlights
  • Offline calorie tracking
  • Built-in Russian food database
  • Log meals by time
  • Track body measurements
  • Add custom foods
  • Sync with Apple Health
Features
Read full description

"Spark: Calorie Counter" — a simple and easy-to-use calorie tracker with Russian language support. The app comes with a built-in food database in Russian and works completely offline. All your data is stored locally on your device, so you can use the calorie counter anywhere — in the countryside, at a summer house, or while traveling — without an internet connection. Key Features: Track daily calorie intake with the option to log meals by time; Keep a log of chest, waist, and hip measurements; Automatically calculate average measurements over time; Add custom foods to the database; Sync weight, calories, macros, water intake, and waist measurements with the Apple Health app. Integration can be enabled or disabled in the settings. If you have any questions, feedback, or suggestions, please leave them at: http://ioscaloriecounter.blogspot.ru/

About

slotho

Features
Read full description

slotho is a food, drink, sleep, workout and fasting diary that also tells you how those things connect. The insights are worked out on your device, and everything you log goes to Apple Health, where it stays yours. LOG IT IN SECONDS - Search a food, scan a barcode, photograph a plate, or type "two eggs and a coffee" - Hundreds of common foods built in, most with their own illustration, plus Open Food Facts and USDA FoodData Central - Drinks log what is actually in them: water, caffeine and alcohol - Meals, favorites and plans you can reuse - Log from Apple Watch, the Home Screen, Siri or a Shortcut - Delete any entry where you see it, with Undo HOW FOOD MAKES YOU FEEL - Six digestion symptoms with severity, where a symptom-free visit counts as evidence too - Ten more symptoms, from headaches to appetite changes - Mood check-ins through Apple Health's State of Mind - GLP-1 Mode: your dose days from Health, with symptoms on the days after a dose compared with later days - slotho looks for foods that show up before a symptom, using only your own logs, and says so only once the evidence is there - Correlations across sleep, digestion, energy, caffeine, alcohol and heart-rate variability - Ask your history in your own words, such as "When did I last eat salmon?", and get the answer from your own logs YOUR DAY IN ONE VIEW - A daily balance from sleep, food, activity and recovery - Energy in against energy spent, plus macros, fiber, sugar and electrolytes - Water, caffeine and alcohol - Home Screen and Lock Screen widgets, and an Apple Watch complication - A report for your dietitian or your trainer, ready to send FASTING - An eating window for each day of the week - Your fast starts when you actually finished eating, not when the schedule said you would - The stage you are in on Today and on your wrist, stage notifications, and a morning recap for the ones you slept through SLEEP, RECOVERY AND MIND - Stages, duration, and how regular your nights are - Resting heart rate and heart-rate variability against your own baseline, never a population figure - Training load: this week against your last four - Breathe, and six guided meditations read aloud WORKOUTS - Build plans on iPhone, run them from your wrist - Timed sets, rests, and exercise notes read aloud on the watch - Sloth Pacing ends a rest when your heart rate has come back, not when a timer says so - Save workouts, nights of sleep, meals and mindful sessions to Calendar - slotho only ever adds events, and never reads your calendar PRIVATE BY DEFAULT - Correlations are worked out on your device - Photos sent for analysis are stripped of location, capture time and camera details first - No account, no advertising, no tracking FREE, AND PRO Free is a complete diary: unlimited food, drink and symptom logging, the fasting timer, unlimited meal and workout plans, breathing and guided meditations, and logging on Apple Watch. PRO adds your daily balance score, the correlations, weekly recaps, your full history, and Sloth Pacing and Coach Voice on the watch. PRO also brings its own AI, with no key of your own: meal photos and typed foods read, foods drawn, meal and workout plans drafted, customized voice meditations and your workout notes voiced, and questions about your history answered, all from one monthly balance of credits. Monthly or yearly, with a free trial. Also on iPad and Mac, kept in step through Apple Health and iCloud. Terms & Conditions: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Spark4 screens
slotho4 screens

Verdict

The call

The clearest difference is update cadence: slotho at every 2 weeks against Spark's monthly. Spark's advantage is iOS requirement (15.6 vs 17.6). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Spark sells 1 one-off in-app purchase and slotho sells 6 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Spark ships an update monthly, slotho every 2 weeks. The most recent releases landed on November 1, 2026 and November 7, 2026 respectively.

Scorecard2 real differences · 8 level
Spark versus slotho: the parameters behind the verdict, then further details
ParameterSparkslotho
PriceFreeFree
Rating3.0 (3 ratings) — better—
Positive reviews69.4% of reviews—
Number of ratings3 — better—
Update frequencyMonthlyEvery 2 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod, Apple Watch — betteriPhone, iPad, Apple Watch
Requires iOS15.6 — better17.6
Further details — not scored
Size38 MB67 MB
Age rating4+12+
DeveloperDmitri MarfinLuiz Carlos Maia Junior

In-app purchases

1 purchases

Spark

One-time1
  • Awesome calorie counter No Ads$3.99
6 purchases

slotho

Subscriptions6
  • slotho PRO Lite (Monthly)1 Month trial$2.991 Month
  • Slotho Pro (Monthly)1 Month trial$6.991 Month
  • slotho PRO+ (Monthly)1 Month trial$12.991 Month
Show 3 more
  • slotho PRO Lite (Yearly)1 Month trial$29.991 Year
  • Slotho Pro (Yearly)1 Month trial$69.001 Year
  • slotho PRO+ (Yearly)1 Month trial$129.991 Year

Questions

Is Spark free?
Spark is free to download, with in-app purchases available.
Is slotho free?
slotho is free to download, with in-app purchases available.
Do Spark or slotho have ads?
Neither Spark nor slotho shows ads.
Which is updated more often, Spark or slotho?
Spark ships an update monthly, and slotho every 2 weeks. Most recently, Spark was updated on November 1, 2026 and slotho on November 7, 2026.

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