Comparison

OpenCap vs Knee Injury Tracker

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

Head to head
About

OpenCap

Capture 3D human movement data using your iOS device's camera. Analyze biomechanics through a comprehensive system including an app, web platform, and cloud computing.

Highlights
  • 3D human movement capture
  • iOS video recording
  • Web-based data collection
  • Biomechanical analysis
  • Cloud computing integration
Features
Read full description

OpenCap is a software system to measure 3D human movement from iOS device videos. It comprises an iOS app for video capture, a web app for data collection and visualization, and scalable cloud computing for biomechanical analysis from video.

About

Knee Injury Tracker

Features
Read full description

Knee Injury Tracker is an AI-powered Knee Tracker app that transforms how healthcare professionals evaluate movement and monitor knee health—no markers, sensors, or wearables required. Designed for physiotherapists, sports professionals, and rehab experts, Knee Injury Tracker provides real-time, in-depth analysis of key knee movement parameters using just a smartphone camera. 1. AI Knee Tracking and kinematic Analysis Knee Injury Tracker advanced knee tracking technology captures precise knee motion and delivers intuitive, easy-to-understand insights. The app measures: Step length, step time, and knee movement symmetry Cadence and step count Time spent in Stance vs. swing phases Progression of knee recovery over time All data is presented with clean, exportable graphs and detailed PDF reports, making it easy to document patient progress or share with colleagues. Supports a wide range of knee injuries and conditions: ACL (Anterior Cruciate Ligament) PCL (Posterior Cruciate Ligament) MCL (Medial Collateral Ligament) LCL (Lateral Collateral Ligament) Post-operative rehabilitation General knee instability and overuse injuries The app provides objective data to guide treatment planning, track progress, and optimize recovery strategies. 2. Real-Time Range of Motion (ROM) Tracking Assess knee flexibility and mobility with live angular reports: Range of Motion Angular Velocity Ideal for monitoring rehab progress and customizing therapy plans. Your privacy comes first. Terms of Use: [https://flexitrace.com/terms&conditions.html]

Screenshots

OpenCap4 screens
Knee Injury Tracker4 screens

Verdict

The call

The clearest difference is in-app purchases: OpenCap at none against Knee Injury Tracker's 8. OpenCap also leads on iOS requirement (15.6 vs 17.0). Knee Injury Tracker's advantage is update cadence (every 4 days vs every 4 months). On price, ads 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. Knee Injury Tracker sells 7 one-off in-app purchases. OpenCap asks for nothing beyond the download.

UpkeepUpdate frequency

OpenCap ships an update every 4 months, Knee Injury Tracker every 4 days. The most recent releases landed on October 25, 2026 and October 2, 2026 respectively.

Scorecard3 real differences · 6 level
OpenCap versus Knee Injury Tracker: the parameters behind the verdict, then further details
ParameterOpenCapKnee Injury Tracker
PriceFreeFree
Rating5.0 (7 ratings) — better—
Number of ratings7 — better—
Update frequencyEvery 4 monthsEvery 4 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better17.0
Further details — not scored
Size6 MB199 MB
Age rating4+4+
DeveloperModel Health, Inc.FlexiTrace Yazilim Ticaret LIMITED SIRKETI

In-app purchases

None

OpenCap

No in-app purchases

7 purchases

Knee Injury Tracker

One-time7
  • 5 Coins$9.99
  • 10 Coins2 variants$17.99
  • 1 Coin$29.99
Show 4 more
  • 5 Coins$69.99
  • 4 Coins$98.99
  • 10 coin pack$119.00
  • 10 Coins$191.99

Questions

Is OpenCap free?
OpenCap is free to download, with no in-app purchases.
Is Knee Injury Tracker free?
Knee Injury Tracker is free to download, with in-app purchases available.
Do OpenCap or Knee Injury Tracker have ads?
Neither OpenCap nor Knee Injury Tracker shows ads.
Which is updated more often, OpenCap or Knee Injury Tracker?
OpenCap ships an update every 4 months, and Knee Injury Tracker every 4 days. Most recently, OpenCap was updated on October 25, 2026 and Knee Injury Tracker on October 2, 2026.

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