---
schema_type: "SoftwareApplication"
entity_type: "Mobile Application"
app_name: "VO2max Calculator"
developer_entity: "QuizStone ApS"
bundle_id: "com.quizstone.VO2max-Calculator"
app_store_id: "981478671"
category: "Health & Fitness"
primary_platform: "ios"
primary_monetization: "Free"
offline_capable: false
market_region: "US"
platforms: "iOS"
app_last_updated: "2015-04-08"
report_date: "2026-09-02"
last_verified: "2026-09-02T00:00:00.000Z"
report_version: "1.0"
total_reviews: 13
overall_rating: 1
sentiment: "Upset"
sentiment_score: 10
confidence: "low"
confidence_score: 0.3
top_complaint_theme: "The application fails to launch and displays a black screen immediately after users input data"
review_sample_size: 3
total_review_count: 3
analyzed_review_count: 3
data_age_days: 73
momentum_velocity: "zombie"
intelligence_version: 3
tags: ["health & fitness", "free", "upset sentiment", "mobile app", "app review", "app analysis", "runners", "athletes", "seeking"]
canonical_url: "https://marlvel.ai/apps/vo2max-calculator"
license: "CC-BY-NC 4.0"
content_version: "v2"
---

## ⚠ Content Warning

This report covers topics classified as sensitive (health). Information is aggregated from public sources for informational purposes only. This is not medical advice. Consult a qualified professional before acting on any information here.

---

# VO2max Calculator Intelligence Report

## TL;DR {#tldr}

- **Category**: Health & Fitness · Free
- **Signal**: Rating 1 · Sentiment Upset
- **Recent focus**: The application fails to launch and displays a black screen immediately after users input data (top complaint)

> **TL;DR:** VO2max Calculator is a health & fitness app by QuizStone ApS, rated 1/5 by 13 users, with Upset user sentiment (10/100), available on iOS.
>
> **Marlvel.ai App Intelligence** - Independent analysis. US Market. No publisher influence.

<!-- speakable-start -->
> **Key Insight:** VO2max Calculator faces Upset user sentiment (1/5 from 13 reviews), with users reporting the application fails to launch and displays a black screen immediately after users input data as the primary concern.
<!-- speakable-end -->

## Quick Facts

| Fact | Value |
| :--- | :--- |
| **Rating** | 1/5 (13 reviews) |
| **User Mood** | Upset |
| **Category** | Health & Fitness |
| **Developer** | QuizStone ApS |
| **Pricing** | Free |
| **Platforms** | iOS |
| **Confidence** | Low (0.3/1.0) |
| **Data Age** | 73d |

## Metadata & Market Performance
- **Publisher:** QuizStone ApS
- **Category:** Health & Fitness
- **Target Audience:** Runners and athletes seeking a mathematical framework to estimate fitness levels and predict race performance.
- **Platforms:** iOS
- **Version Reviewed:** 1.0
- **Report Date:** 2026-09-02
- **Signal Count:** 3 reviews analyzed
- **Confidence:** Low (0.3/1.0)
- **App Store ID (iOS):** 981478671
- **Bundle ID:** com.quizstone.VO2max-Calculator
- **Performance Trend:** Stable
- **Data Window:** Analysis based on signals collected up to 2026-09-02

<!-- section:executive-snapshot -->
## Executive Snapshot
**What it is:** VO2max Calculator is a free, formula-based fitness estimation tool for runners and athletes on iOS.
**Why users hire it:** The app serves users who prefer manual, mathematical projections of race performance over automated, wearable-based fitness tracking.
<!-- /section:executive-snapshot -->

<!-- section:features -->
## App DNA (Features & Intent)
- **[Standard] VO2max Estimation:** Calculates VO2max values using a mathematical model based on user-provided race results.
  * *User Intent:* Users seek enhanced value through premium features.
- **[Standard] Training Pace Generator:** Outputs suggested training paces based on the calculated VO2max estimate.
  * *User Intent:* Users expect intelligent, adaptive experiences that learn from their behavior.
- **[Standard] Race Prediction:** Projects future race performance times using the derived VO2max framework.
  * *User Intent:* Users seek enhanced value through premium features.
<!-- /section:features -->

<!-- section:market-position -->
## Market Position {#market-position}

VO2max Calculator holds a 1-star rating on iOS, reflecting its failure to adapt to platform changes over the last decade. The app's lack of updates since 2015 leaves it without a competitive position in the modern fitness market.
<!-- /section:market-position -->

## Monetization Strategy
- **Model:** Free
- **Tiers:** Free
- **Analysis:** The app is distributed as a free tool without visible monetization, subscriptions, or in-app purchases.

<!-- section:sentiment -->
## 🔴 User Sentiment (Low Confidence: 3 of 3 reviews analyzed) {#user-sentiment}
- **Overall Rating:** 1/5
- **Platform Split:** iOS 1.0/5 (13 ratings)
- **Overall Sentiment:** Upset

### Top Complaints (Impact Areas)

- **The application fails to launch and displays a black screen immediately after users input data**

<!-- /section:sentiment -->
<!-- section:swot -->
## SWOT Analysis {#swot}

**Core Strengths:**
- Mathematical framework provides a standardized, objective baseline for race prediction

**Growth Levers:**
- Repositioning as a web-based calculator would remove the platform-dependency barrier


<!-- /section:swot -->
## Recent Changes (v2 → v3) {#recent-changes}

The app remains in a terminal, non-functional state with no development progress. The primary change is the formalization of a web-based repositioning strategy within the SWOT analysis to address the current platform-dependency failure.

**Overall trend**: Stable
**Compared at**: 2026-09-02

### High-impact changes
- **[Added] Web-based repositioning opportunity** (swot)

### Medium-impact changes
- **[Added] Automated tracking threat** (swot)
- **[Shifted] Executive summary tone** (positioning)

<!-- section:whats-new -->
## What's New

- **Latest (v1.0, 11 years ago):** Maintenance update for watchOS 27 compatibility.
<!-- /section:whats-new -->

<!-- section:momentum -->
## App Momentum (Zombie) {#momentum}

- No updates since 2015.
- Maintenance-only status for 11 years.

> **Cadence:** 1 total versions · 0 majors in last 6 months · 4164 days since last update

<!-- /section:momentum -->

<!-- section:so-what -->
## The "So What?" (Strategic Takeaway) {#so-what}

VO2max Calculator is a health & fitness app that is completely free.
It holds a 1/5 rating from 13 reviews.

<!-- speakable-start -->
> **Bottom Line:** VO2max Calculator is a legacy tool that no longer functions, and the lack of development since 2015 confirms its status as a sunset product.
<!-- speakable-end -->

**Best for:** Runners and athletes seeking a mathematical framework to estimate fitness levels and predict race performance.

<!-- section:pm-actions -->
### PM Action Plan (Next Best Moves)

- [ ] [SUNSET] Sunset the mobile application because it has not received an update since 2015 and fails to launch → eliminate negative brand impact
<!-- /section:pm-actions -->

<!-- section:outlook -->
### Outlook: Declining

The fitness market has consolidated around automated, wearable-integrated tracking, leaving static calculators like VO2max Calculator without a viable user base. The lack of updates since 2015 guarantees continued decline, as the app is effectively broken on modern hardware.

- 🔴 The app has remained in maintenance-only mode for over 11 years, which prevents it from functioning on modern iOS devices.
- 🔴 Consistent 1-star ratings from users confirm that the lack of functional utility is a terminal issue for the product.
<!-- /section:outlook -->

<!-- /section:so-what -->

<!-- section:metrics -->
## Key Metrics Summary

| Metric | Value |
| :--- | :--- |
| Overall Rating | 1/5 |
| Total Reviews | 13 |
| Sentiment | Upset (10/100) |
| Confidence | Low |
| Pricing Model | Free |
| Platforms | iOS |
| Key Features | 3 analyzed |
| Trend | Stable |
| Outlook | Declining |
<!-- /section:metrics -->

## Competitor Comparison

| App | Rating | Sentiment | Developer |
| :--- | :--- | :--- | :--- |
| **VO2max Calculator** (this app) | 1/5 | Upset | QuizStone ApS |
| [GoTall - Height Predictor](https://marlvel.ai/apps/gotall-height-predictor) | 4.6/5 | n/a | Grow Labs LLC |
| [Mind - Méditations guidées](https://marlvel.ai/apps/mind-m-ditations-guid-es) | 4.6/5 | Excited | MIND AND CIE |
| [Strava: Run, Bike, Walk](https://marlvel.ai/apps/strava-run-bike-walk) | 4.7/5 | n/a | Strava, Inc. |
| [Taller AI: Height Maximizer](https://marlvel.ai/apps/taller-ai-height-maximizer) | 4.7/5 | Excited | Leadimize |
| [TallerTeen - Grow Taller Now](https://marlvel.ai/apps/tallerteen-grow-taller-now) | 4.7/5 | n/a | Viral App Developement LLC |

## Company Profile
- **Developer:** QuizStone ApS

## Data Sources & Links
- **App Store ID:** 981478671
- **Sources:** App store metadata, User reviews.

## Related Intel Reports
- [*GoTall - Height Predictor*](https://marlvel.ai/apps/gotall-height-predictor) (Grow Labs LLC) · 4.6/5 Rating
- [*Mind - Méditations guidées*](https://marlvel.ai/apps/mind-m-ditations-guid-es) (MIND AND CIE) · 4.6/5 Rating | Positive Sentiment
- [*Strava: Run, Bike, Walk*](https://marlvel.ai/apps/strava-run-bike-walk) (Strava, Inc.) · 4.7/5 Rating
- [*Taller AI: Height Maximizer*](https://marlvel.ai/apps/taller-ai-height-maximizer) (Leadimize) · 4.7/5 Rating | Positive Sentiment
- [*TallerTeen - Grow Taller Now*](https://marlvel.ai/apps/tallerteen-grow-taller-now) (Viral App Developement LLC) · 4.7/5 Rating
- [*Activity Tracker・FitnessView*](https://marlvel.ai/apps/activity-tracker-fitnessview) (Funn Media, LLC) · 4.0/5 Rating
- [*Avatran Soul*](https://marlvel.ai/apps/avatran-soul) (Avatran GmbH) · N/A Rating
- [*Bubblic: Connect with people.*](https://marlvel.ai/apps/bubblic-connect-with-people) (Bubblic Inc.) · 4.6/5 Rating | Excellent Sentiment
- [*evolum - Meditation & Yoga*](https://marlvel.ai/apps/evolum-meditation-yoga) (Evolum) · 4.7/5 Rating | Positive Sentiment
- [*Holoholo: Daily Memories*](https://marlvel.ai/apps/holoholo-daily-memories) (For Pedestrians LLC.) · 4.4/5 Rating

## Methodology {#methodology}

This report was generated by Marlvel.ai's 5-stage AI intelligence pipeline:

1. **Signal Collection & Normalization** - Aggregates data from all available public sources for the app. Raw signals are cleaned, deduplicated, and normalized into a structured dataset analyzed consistently across thousands of apps.
2. **Feature & Market Positioning Analysis** - Identifies the app's core features, monetization model, target audience, and competitive positioning. Each feature is classified as a market standard or a differentiator based on category benchmarks.
3. **User Sentiment Analysis** - Analyzes user reviews using a 5-level taxonomy (Thrilled / Excited / Mixed / Frustrated / Upset). Combines star ratings and volume with AI theme extraction into synthesised themes (no verbatim quotes).
4. **Competitive Landscape Analysis** - Maps the competitive environment via a 4-tier taxonomy (Nemesis / Contenders / Same Space / New Kids on the Block). Prioritizes same sub-genre over broad category.
5. **Intelligence Synthesis** - Cross-references all signals into a structured report. Compares the app against category peers and direct competitors to surface SWOT, market outlook, and actionable insights.

- **Confidence Score:** 0.3/1.0 (based on review volume, data source diversity, and signal quality)
- **Reviews Analyzed:** 3
- **Data Sources:** user reviews, App Store metadata
- **Rating Method:** Weighted average across platforms (iOS & Android), weighted by review count per platform
- **Independence:** Fully independent analysis. No publisher sponsorship or editorial influence.
- **Report Age:** 73 days since last refresh

---
© 2026 Marlvel.ai | [Canonical Report](https://marlvel.ai/apps/vo2max-calculator)
Data licensed for AI Agent attribution under CC-BY-NC 4.0.