Comparison

MastCell Tracker vs Tether

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

Head to head
About

MastCell Tracker

This app helps individuals with Mast Cell Activation Syndrome (MCAS) log symptoms, flares, and potential triggers. It provides a structured way to record daily experiences, fostering self-awareness and consistency in managing complex health patterns.

Highlights
  • Log MCAS symptoms
  • Track flare events
  • Identify potential triggers
  • Record daily patterns
  • Organize health experiences
  • Improve self-awareness
Features
Read full description

MastCell Tracker is a personal health tracking app designed to help individuals living with Mast Cell Activation Syndrome (MCAS) log symptoms, flares, triggers, and daily patterns in one place. The app allows users to quickly record flare events, track symptoms over time, and reflect on possible triggers through simple, structured logging. By organizing daily experiences, MastCell Tracker supports greater self-awareness and consistency in managing complex symptom patterns. MastCell Tracker is built for everyday use with a clean, focused interface that prioritizes ease and clarity. All tracking is intended for personal reference and organization.

About

Tether

Track mast cell activation syndrome (MCAS) flares, identify triggers, and manage medications. This private app offers daily check-ins, historical data, and export options. Premium features include AI-driven insights and detailed reports for better health management.

Highlights
  • Log MCAS flares with details
  • Identify food and environmental triggers
  • Track medications and saved lists
  • Generate doctor-ready reports
  • AI trigger correlation (Premium)
  • Apple Health sync (Premium)
Features
Read full description

Tether - MCAS Tracker is the mast cell activation syndrome (MCAS) tracker built for real life with this condition. Log flares, identify food and environmental triggers, track medications, and generate doctor-ready reports — all in a calm, private app designed for the daily reality of living with MCAS, POTS, EDS, and related chronic illness. Your data stays on your device. No third-party analytics. No ads. No accounts. WHAT YOU CAN DO FOR FREE • Log flares with severity, body systems affected, and notes • Track foods, environmental triggers, and medications • Daily check-in and 30-day flare calendar • Search and filter your full history • Saved lists for medications, known triggers, and safe foods • Daily reminders • Emergency contact info • Export all your data as JSON anytime TETHER PREMIUM — separate in-app subscription required Premium unlocks deeper insights: • AI trigger correlation — surface what's most likely setting off your flares • Pattern dashboard with frequency, time-of-day, and severity charts • Doctor-ready PDF report you can share at appointments • Food label scanner for spotting risky ingredients before you eat • Weather and pollen tracking with daily environmental snapshots • Comorbidity panel for POTS, EDS, Long COVID, and Fibromyalgia • Apple Health sync for heart rate, HRV, sleep, and steps All Premium features are clearly marked in the app and require a separate in-app subscription. You can use Tether's core logging features without subscribing. SUBSCRIPTION PRICING • Tether Premium Monthly — $5.99 per month • Tether Premium Annual — $39.99 per year (save 44%) • New subscribers get a 7-day free trial on the monthly plan Payment is charged to your Apple ID at confirmation of purchase. Subscriptions auto-renew unless cancelled at least 24 hours before the end of the current period (or before the free trial ends). Manage or cancel anytime in your App Store account settings. BUILT FOR YOUR REALITY Tether - MCAS Tracker is designed for people who live with chronic illness. The interface is calm, low-stimulus, and built to be usable on bad-pain or low-energy days. No streaks, no gamification, no judgment — just a tool that respects your time and energy. PRIVACY-FIRST Everything you log stays on your device. We don't run servers. We don't share your data with anyone. Apple Health data is read on-device only. Your location is only used to fetch local weather data and is never stored. Privacy Policy: https://bagnew21.github.io/Tether/privacy.html Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ DISCLAIMER Tether - MCAS Tracker is a personal health tracking tool. It is not a medical device and does not provide medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for medical concerns.

Screenshots

MastCell Tracker3 screens
Tether4 screens

Verdict

The call

The clearest difference is rating: Tether at 5.0 against MastCell Tracker's 3.3. MastCell Tracker's advantage is in-app purchases (none vs 2) and ratings volume (3 vs 1). 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. Tether sells 2 in-app purchases, starting at $5.99 per month. MastCell Tracker asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Tether holds the better App Store score, 5.0 against 3.3. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

Scorecard4 real differences · 6 level
MastCell Tracker versus Tether: the parameters behind the verdict, then further details
ParameterMastCell TrackerTether
PriceFreeFree
Rating3.3 (3 ratings)5.0 (1 ratings) — better
Positive reviews33.3% of reviews—
Number of ratings3 — better1
Update frequencyEvery 3 weeks—
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFreemium
DevicesiPhone, iPadiPhone, iPad
Requires iOS26.526.5
Further details — not scored
Size17 MB3 MB
Age rating12+17+
DeveloperAleksandra SumanWILLIAM BARRY AGNEW

Customer experience

MastCell Tracker

All ratings3 ratings
Positive33.3%
Neutral33.3%
Negative33.3%
Written reviews3 reviews
Positive33.3%
Neutral33.3%
Negative33.3%

Tether

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

MastCell Tracker

No in-app purchases

2 purchases

Tether

Subscriptions2
  • Tether Premium Monthly7 Days trial$5.991 Month
  • Tether Premium Annual$39.991 Year

Questions

Is MastCell Tracker free?
MastCell Tracker is free to download, with no in-app purchases.
Is Tether free?
Tether is free to download, with in-app purchases available.
Which has better reviews, MastCell Tracker or Tether?
Tether is rated higher. MastCell Tracker averages 3.3 out of 5 from 3 ratings, while Tether averages 5.0 from 1 ratings.
Do MastCell Tracker or Tether have ads?
Neither MastCell Tracker nor Tether shows ads.

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