Comparison

The Deficit vs Simple Muscle

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

Head to head
About

The Deficit

Features
Read full description

Understand your calorie balance. Log food your way. The Deficit brings your calorie intake, energy expenditure and progress together in a clear daily overview, using Apple Health data from the apps and devices you already use. SEE THE BIG PICTURE • Follow your calorie balance across days and custom date ranges. • See intake, macros, resting and active energy, and exercise. • Set a goal and compare your estimated progress. Days with incomplete intake can be excluded from the balance calculation. AGENTIC FOOD TRACKING — OPTIONAL, EFFORTLESS Tell the AI agent what you eat and it logs the meal for you. Dictate foods and amounts, or photograph a nutrition label and say or type “Log 200 g of this food.” The agent reads the label, calculates the portion and adds it to your diary. When you do not know the portion, it can estimate it for you to review and adjust. • Log meals by typing, dictating or taking a photo on iPhone or iPad. • Log multiple meals at different times in one request. • Dictate food and review your diary directly on Apple Watch. • Ask follow-up questions in chat or start a live voice conversation. • Add a personal coaching goal for more relevant feedback. • Review and edit portions and nutrition values. • Reuse familiar foods from your food memory. • Keep your diary and conversation in sync across iPhone, iPad and Apple Watch. • Start dictation with Shortcuts or the Action Button on supported devices. KEEP YOUR EXISTING TRACKER Prefer another food app? Turn off food tracking and continue using The Deficit as your Apple Health calorie-balance overview. YOUR CHOICES Sign in with Apple keeps your account connected across devices. Onboarding explains OpenAI processing when you use AI features. Apple Health access and optional transcript sharing remain under your control in Settings. You can turn off food tracking and delete your account in the app. AI uses credits. New accounts receive welcome credits; additional packs are available as one-time in-app purchases. Purchased credits do not expire while your account exists. At zero credit, AI pauses; your existing data and manual features remain available. Internet access is required for AI and cloud synchronization. Nutrition values and projected weight changes are estimates. Check suggested foods and portions before relying on them. The Deficit is not a medical device and does not provide medical diagnosis or treatment.

About

Simple Muscle

Log your gym sets efficiently with this AI-powered workout tracker. Plan routines, track reps, weight, and time, and manage rest periods with on-wrist Apple Watch support. Explore a vast exercise library and visualize your progress.

Highlights
  • AI-native workout tracking
  • Apple Watch integration
  • Rest timer with Lock Screen notifications
  • Library of 400+ exercises
  • Progress charts and session history
  • Optional AI Connection subscription
Features
Read full description

Simple Muscle is an AI-native workout tracker built for the moments between sets—now on iPhone and Apple Watch—and for the AI chat you already use. Plan a workout once, then log each set quickly with clear controls for reps, weight, or time. Move between exercises, add extra sets, and manage recovery with a rest timer that follows your workout to the Lock Screen and Dynamic Island. Take your saved workouts to Apple Watch and train without carrying your phone. Follow your workout exercise by exercise, adjust weight, reps or duration, complete sets, and manage rest periods directly from your wrist. The core tracker is free and works offline. Create workouts, explore a library of more than 400 exercises, review session history, check weekly volume, view progress charts, adjust kg/lb and rest settings, and complete workouts without an account. Optionally save completed workouts to Apple Health so they appear in your activity history. If you sign in, optional sync can back up and restore your training data across devices. With the optional AI Connection subscription, Simple Muscle can connect to ChatGPT, Claude, or other MCP-compatible assistants so an assistant you authorize can plan, edit, and analyze workouts using your training history. Features: - Apple Watch workout tracking - Workout templates and custom workout creation - Active workout mode with exercise and set progress - Reps, weight, and duration tracking - Rest timer with pause and end-rest controls - Library of more than 400 exercises - Exercise filters, instructions, videos, and common mistakes - History, weekly summaries, session details, and progress charts - Kg/lb and week-start preferences - Lock Screen Live Activities and rest notifications - Optional Apple Health workout saving - Optional account sync and AI Connection Simple Muscle is intended for personal fitness tracking and does not provide medical advice. Exercise involves risk. Choose appropriate movements and loads, stop if something feels unsafe, and consult a qualified professional before starting or changing a program when needed. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

The Deficit4 screens
Simple Muscle4 screens

Verdict

The call

The clearest difference is in-app purchases: The Deficit at none against Simple Muscle's 2. The Deficit also leads on update cadence (weekly vs fortnightly). On price, ads, device support and iOS requirement 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. Simple Muscle sells 2 in-app purchases, starting at $4.99 per month. The Deficit asks for nothing beyond the download.

UpkeepUpdate frequency

The Deficit ships an update weekly, Simple Muscle fortnightly. The most recent releases landed on October 27, 2026 and October 28, 2026 respectively.

Scorecard2 real differences · 8 level
The Deficit versus Simple Muscle: the parameters behind the verdict, then further details
ParameterThe DeficitSimple Muscle
PriceFreeFree
Rating—1.0 (1 ratings) — better
Positive reviews—0.0% of reviews
Number of ratings—1 — better
Update frequencyWeekly — betterFortnightly
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Freemium
DevicesiPhone, iPad, Apple Watch — betteriPhone, Apple Watch
Requires iOS17.517.0 — better
Further details — not scored
Size34 MB124 MB
Age rating12+12+
Developer5 LADISLAV HRBACEKVladimir Haltakov

In-app purchases

None

The Deficit

No in-app purchases

2 purchases

Simple Muscle

Subscriptions2
  • Simple Muscle Monthly Plan$4.991 Month
  • Simple Muscle Yearly Plan$49.991 Year

Questions

Is The Deficit free?
The Deficit is free to download, with no in-app purchases.
Is Simple Muscle free?
Simple Muscle is free to download, with in-app purchases available.
Do The Deficit or Simple Muscle have ads?
Neither The Deficit nor Simple Muscle shows ads.
Which is updated more often, The Deficit or Simple Muscle?
The Deficit ships an update weekly, and Simple Muscle fortnightly. Most recently, The Deficit was updated on October 27, 2026 and Simple Muscle on October 28, 2026.

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