Comparison

4D Motion vs GPS Twin Odometers

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

Head to head
About

4D Motion

Learn, analyze, and train human motion for sports, conditioning, and physical therapy. Features interactive 3D tutorials, swing analysis by comparing your recordings to pro models, and motion capture for detailed performance training and rehabilitation.

Highlights
  • Interactive 3D golf tutorials
  • Compare your motion to pro models
  • Record and overlay your video with 3D models
  • 3D motion capture for analysis
  • Performance training and physical therapy tools
  • Analyze golf, baseball, and conditioning movements
Features
Read full description

4D Motion is the ultimate 3D platform for learning, analyzing and training human motion for sports, conditioning and physical therapy. *New for Golf* · An interactive golf tutorial featuring pro swings in 3D. You can see their swings from any angle, zoom in and out and see exactly what they are doing without the limitations of 2D video. Included are tips highlighting key positions or movements for each step of the swing. · Compare your movement to a pro’s. Record a video of your swing right from your phone and overlay a pro’s 3D model on top of your video from address to finish. This revolutionary technology will instantly highlight the changes you need to make to improve your swing, Use 4D Motion sensors to capture yourself or your students in 3D to train like a professional. Use 4D Motion sensors to measure and analyze/compare movements in 3D for physical therapy, rehabilitation and performance training. For golf, baseball, performance training, and physical therapy, 4D Motion is the most sophisticated, yet simple and affordable platform to analyze, learn, and train human motion. Download this free app and try it risk-free.

About

GPS Twin Odometers

This app provides dual odometers, clocks, and stopwatches for historic, classic, and vintage road rallies. It uses device GPS for accurate distance measurement and offers multiple modes for timing and tracking stages. Log your data with geographic coordinates for detailed record-keeping.

Highlights
  • Dual odometers with two decimal place accuracy
  • Integrated stopwatch and clock functions
  • GPS-based distance measurement
  • Three operational modes: Regularity, Jogularity, Lap
  • Distance logging with geographic coordinates
  • Option to subtract distance when off-course
  • Choice between miles or kilometers
Features
Read full description

Historic, Classic, or Vintage road rallies may permit digital dual odometers, clocks, and stopwatches. This app combines all three using timers and GPS devices built into Apple mobile devices. GPS inputs are used strictly for distance measures along the rally route. Also, the displayed accuracy of two decimal places conforms to typical historic, classic, and vintage road rally restrictions. However, it is possible to interpolate distance to three decimal places. There are tick marks to indicate the second decimal place number centered on the display as well as increments of +0.0025, +0.0050, and +0.0075. When touched, the Control button will pause the two odometers for 4 seconds to allow you time to estimate distance to thousandths. Similarly, time measurements are limited to whole seconds or cents. Time, distance, and mode (discussed below) may be chosen at the start of a new rally by touching the Set button to access app Settings. A set of buttons allows you to chose the active odometer. The leftmost button activates the lower "interval distance" odometer; the rightmost button activates the upper "total distance" odometer; the center button activates both odometers. From time to time you may measure time and distance for a stage or a checkpoint and record data by touching the Control button. The time and distance will be stored in a log along with geographic coordinates. Distance options include subtraction of distance when you travel off course. Direction buttons switch between forward (+), reverse (–), and park (0). Also, you may chose between miles or kilometers. There are three modes of operation selectable in the app Settings: Regularity mode, Jogularity mode, and Lap mode. In Regularity mode, the stopwatch will be reset to zero each time the Control button is pressed. In Jogularity mode the time split will be recorded but the stopwatch will continue recording. In Lap mode, the tabular display will reset the stopwatch to zero when the control button relabeled Lap Reset is touched and each split time will be identified as a Lap in the table. Also, in Lap mode, the options to zero either of the odometers are removed, however the lower odometer can be set to zero at the start of each lap by touching the Lap Reset button. Note: Use of the GPS Twin Odometers during any particular rally will be subject to the rules and instructions governing the rally and may define your category or class among participants. Please consult the Rally Master for approval of the use of this app. Disclaimer: Continued use of GPS running in the background can dramatically decrease battery life.

Screenshots

4D Motion4 screens
GPS Twin Odometers3 screens

Verdict

The call

The clearest difference is price: 4D Motion at Free against GPS Twin Odometers's $12.99. 4D Motion also leads on rating (3.8 vs 3.0) and update cadence (monthly vs every 7 months). GPS Twin Odometers's advantage is in-app purchases (none vs 6). On review sentiment, 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

4D Motion is free to download; GPS Twin Odometers costs $12.99 up front. 4D Motion sells 6 one-off in-app purchases. GPS Twin Odometers asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

4D Motion holds the better App Store score, 3.8 against 3.0. That said, the two scores are not equally well evidenced: 4D Motion has 27 ratings behind it against 2, so its average is the more settled of the two. Written reviews split almost evenly too, at 50% and 50% positive.

UpkeepUpdate frequency

4D Motion ships an update monthly, GPS Twin Odometers every 7 months. Both last shipped on November 2, 2026.

Scorecard6 real differences · 4 level
4D Motion versus GPS Twin Odometers: the parameters behind the verdict, then further details
Parameter4D MotionGPS Twin Odometers
PriceFree — better$12.99
Rating3.8 (27 ratings) — better3.0 (2 ratings)
Positive reviews50.0% of reviews50.0% of reviews
Number of ratings27 — better2
Update frequencyMonthly — betterEvery 7 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
DevicesiPhone, iPad, iPod, Apple Watch — betteriPhone, iPad, iPod
Requires iOS14.013.6 — better
Further details — not scored
Size420 MB1 MB
Age rating12+4+
DeveloperSsam Sports, Inc.MSYapps

Customer experience

4D Motion

All ratings26 ratings
Positive73.1%
Neutral0.0%
Negative26.9%
Written reviews4 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

GPS Twin Odometers

All ratings2 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews2 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

In-app purchases

6 purchases

4D Motion

One-time6
  • Unlock 3D video comparison$0.99
  • 10 swing pack$2.99
  • Unlock more swings$4.99
Show 3 more
  • 30 swing pack$6.99
  • 80 swing pack$15.99
  • 750 swing pack$99.99
None

GPS Twin Odometers

No in-app purchases

Questions

Is 4D Motion free?
4D Motion is free to download, with in-app purchases available.
Is GPS Twin Odometers free?
GPS Twin Odometers costs $12.99, with no in-app purchases.
Which has better reviews, 4D Motion or GPS Twin Odometers?
4D Motion is rated higher. 4D Motion averages 3.8 out of 5 from 27 ratings, while GPS Twin Odometers averages 3.0 from 2 ratings.
Do 4D Motion or GPS Twin Odometers have ads?
Neither 4D Motion nor GPS Twin Odometers shows ads.
Which is updated more often, 4D Motion or GPS Twin Odometers?
4D Motion ships an update monthly, and GPS Twin Odometers every 7 months. Most recently, 4D Motion was updated on November 2, 2026 and GPS Twin Odometers on November 2, 2026.

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