X3 Tracker vs Undersun Fitness
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
X3 Tracker
This is the official free workout tracking tool designed for the Jaquish Biomedical X3® exercise device. It helps users log and monitor their progress while using the specialized equipment.
- Official workout tracking
- Compatible with X3 device
- Free to use
- Log exercise progress
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The Official free workout tracking tool for use with the Jaquish Biomedical X3® exercise device.
Undersun Fitness
Access expert-designed workout programs for all fitness levels, usable anywhere. Follow day-by-day plans with video demonstrations of proper exercise form to build muscle or lose fat.
- Day-by-day workout breakdown
- Expert trainer guidance
- Video tutorials for exercises
- Build muscle or lose fat
- Workout anywhere (home, gym, outdoors)
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BENEFITS OF TA2 DIGITAL PROGRAMS TA2 digital programs work for both beginners and experienced users and can be done anywhere – at home, outdoors or at the gym. All programs include: Day-by-day breakdown of all workouts. Expert trainer taking you through every exercise, set and rep. Video tutorials demonstrating proper form on all exercises.Build muscle or lose fat, at home or at gym, with one of these expert-designed, easy-to-follow TA2 workout programs. *All payments will be paid through your iTunes Account and may be managed under Apple Subscriptions after the initial payment. Subscription payments will automatically renew unless deactivated at least 24-hours before the end of the current cycle. Your account will be charged for renewal at least 24-hours prior to the end of the current cycle. Any unused portion of your free trial will be forfeited upon payment. Cancellations are incurred by disabling auto-renewal. This app is proudly powered by VidApp. If you need help with it, please head to: https://vidapp.com/app-vid-app-user-support Terms of Service: http://vidapp.com/terms-and-conditions Privacy Policy: https://vidapp.com/privacy-policym/app-vid-app-user-support
Screenshots
Verdict
The clearest difference is in-app purchases: X3 Tracker at none against Undersun Fitness's 5. X3 Tracker also leads on rating (3.3 vs 2.9) and update cadence (every 3 weeks vs every 2 months). On price, review sentiment, ratings volume and ads 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
Both are free to download. Undersun Fitness sells 5 in-app purchases, starting at $9.99 per month. X3 Tracker asks for nothing beyond the download.
X3 Tracker holds the better App Store score, 3.3 against 2.9. Both are backed by a comparable volume of ratings — 23 and 51 respectively. Written reviews point the same way: 38% of X3 Tracker's written reviews are positive against 34% of Undersun Fitness's.
X3 Tracker ships an update every 3 weeks, Undersun Fitness every 2 months. Both last shipped on November 3, 2026.
| Parameter | X3 Tracker | Undersun Fitness |
|---|---|---|
| Price | Free | Free |
| Rating | 3.3 (23 ratings) — better | 2.9 (51 ratings) |
| Positive reviews | 37.9% of reviews — better | 33.6% of reviews |
| Number of ratings | 23 | 51 — better |
| Update frequency | Every 3 weeks — better | Every 2 months |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free — better | Free with in-app purchases |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 16.4 | 15.0 — better |
| Further details — not scored | ||
| Size | 67 MB | 105 MB |
| Age rating | 12+ | 4+ |
| Developer | Jaquish Biomedical Corporation | Heros Life LLC |
Customer experience
X3 Tracker
Undersun Fitness
Bugs and requests
X3 Tracker
Not enough reviews yet to summarise bugs or requests.
Undersun Fitness
Reported bugs
18 issues- App crashes between workout modules
- Videos don't load or get stuck buffering
- Password reset email links don't work
- Login credentials not recognized despite valid account
- Error 500 server errors
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- SSL certificate errors preventing access
- Workout progress not saved after app crashes
- Exercise pictures don't match descriptions
- Videos play from middle instead of beginning
- Skips rest periods between exercises
- Doesn't recognize completed workouts
- Timezone changes corrupt workout schedule
- Discount codes don't work
- Separate app and website account systems
- Videos don't play for specific programs (e.g., arm day)
- Band selection options missing for certain exercises
- Incorrect exercise order in programs
- Notification reminders appear after workouts completed
Requested features
14 requests- Ability to view previous workout data during current workout
- Edit logged reps and band selections after submission
- Landscape mode support for tablets
- Apple Watch and Apple Health integration
- Offline/downloadable content for no-internet workouts
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- Text-only workout option without auto-playing videos
- Flexible workout scheduling with time changes
- Weekly and monthly workout summaries
- Better band stacking tracking for multiple bands
- Deferred workout reminders
- Notes feature for each set
- Improved calendar interface with better visualization
- Web-based backup synchronized with app
- More diverse exercise options and advanced programs
In-app purchases
X3 Tracker
No in-app purchases
Undersun Fitness
- Monthly Access7 Days trial$9.991 Month
- Yearly Access7 Days trial$69.991 Year
- TA2 Bodyshock$39.99
- TA2 Build$59.99
- TA2 SIZE-ON$59.99
Questions
Is X3 Tracker free?
Is Undersun Fitness free?
Which has better reviews, X3 Tracker or Undersun Fitness?
Do X3 Tracker or Undersun Fitness have ads?
Which is updated more often, X3 Tracker or Undersun Fitness?
Other comparisons
