FastR vs Log Dyno
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
FastR
Measure your vehicle's acceleration performance with this app. It automatically tests 0-60 and quarter-mile times with millisecond accuracy. Compete with others on a real-time leaderboard and save results for different car models.
- Hands-free, automated acceleration testing
- 0-60 and Quarter mile time measurement
- Millisecond accuracy
- Real-time user ranking
- Save times for different car models
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FastR is the #1 vehicle acceleration performance app in the game! Test your vehicle's 0-60 and Quarter mile times, in a hands-free, fully automated manner. You can also post your acceleration times to our leaderboard to earn bragging rights. - Features accuracy to the millisecond - Displays your rank amongst other users in real time - Lets you save acceleration times from different car models See how your vehicle's acceleration performance compares with others.
Log Dyno
This app analyzes your car's datalog files to measure torque and horsepower using your mobile device. It provides detailed analysis, recommends optimal gear shifts, and allows comparison of multiple measurements.
- Measure torque and horsepower from datalogs
- Virtual dyno analysis
- Optimal gear shift recommendations
- Compare multiple measurements
- Supports various datalog file formats
- Customizable vehicle data input
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Measuring your car's torque and horsepower has never been easier, now that you can do it with the help of your mobile device and this digital Dyno. You just need to open your datalog of a pull, and Log Dyno will do the rest. You can send your CSV file from your email, browser, or any app to Log Dyno which will Open the datalog from the app right away and give you a measurement, or you can save your CSV file to the Log Dyno folder in your Files app, for easy access from the in-app file browser. You can use any CSV or MSL file that contains RPM data which is needed to accurately measure Horsepower and Torque. From the torque curve and gear ratios, the app will also recommend optimal gear shift points for each gear to ensure maximum acceleration. This makes sure you know when to shift, so you always have the most possible power at the wheels. Corrections: ● Uncorrected ● SAE J1349 ● STD ● DIN 70020 ● ISO 1585 Power Units: ● WHP ● BHP ● PS ● KW Torque Units: ● LB-FT ● NM Either at the wheels or at the crank Compare multiple measurements! You can save each one of your Dyno measurements, and compare them, or just analyze them interactively. What datalog files can be used? ● JB4 ● MHD ● ProTool ● COBB ● MegaSquirt ● ProTool ● Bootmod3 ● and any other CSV file This is the easiest way to have your torque and horsepower measured with a virtual dyno using only your mobile phone and your datalog. You can see if your mods or tune work right away, and compare them. Log Dyno has been compared to multiple real life dyno sheets, and measurements were spot on, with multiple different vehicles How does it work? #1. Datalog your vehicle Take the log just like a dyno pull, in one given gear, from low rpm to high rpm. Try to avoid wheelspin as it can cause spikes in the graph. #2. Set up your vehicle data The dyno app requires some data about your vehicle. You’ll be asked to set values for the following: ● Car Name ● Weight ● Tank Capacity ● Tire Size ● DT% ● Drag Coefficient ● Frontal Area #3. Share the results! You can share your results right from the virtual dyno measurement page to basically any app or post it to any social network or email it. Of course, you can just save the results in your phone gallery too. How accurate is the dyno measurement? If you have set your vehicle data correctly, the results our dyno app gives will be the same as the results a real dyno will give you. Also, keep in mind that wheelspin may result in spikes in the graph. If you are unable to avoid it, you’ll still get accurate results, you just need to ignore the spikes. The best thing about our dyno app is that you can see right away how your mods work after datalogging. Now, you don't have to go to the dyno if you want to measure any small modification or just never had your car's power measured. You can see right away how your mods or tune work after datalogging. You can dyno unlimited times and unlimited vehicles for the fraction of the price of a dyno measurement. You have to set your car up, how much it weighs, its tire size, the gear ratios, and also what your car drag coefficient and frontal area are, which the app will help in determining. After specifying for which gear you had the datalog taken and specifying the driver, passenger, and possible cargo weight, you can open the CSV or MSL file. Based on your car data and environmental values, the app generates a torque and horsepower curve, which you can analyze. The app also points out the peak values, and you will be able to see at what rpm you made the most torque and the most power. If you have any questions feel free to send an email: profisoftgames@gmail.com
Screenshots
Verdict
The clearest difference is price: FastR at Free against Log Dyno's $13.99. FastR also leads on rating (4.4 vs 3.4) and review sentiment (38% vs 15%). Log Dyno's advantage is in-app purchases (none vs 2) and iOS requirement (9.0 vs 15.0). On update cadence, 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
FastR is free to download; Log Dyno costs $13.99 up front. FastR sells 2 one-off in-app purchases. Log Dyno asks for nothing beyond the download.
FastR holds the better App Store score, 4.4 against 3.4. That said, the two scores are not equally well evidenced: FastR has 319 ratings behind it against 10, so its average is the more settled of the two. Written reviews point the same way: 38% of FastR's written reviews are positive against 15% of Log Dyno's.
FastR ships an update every 5 months, Log Dyno every 4 months. Both last shipped on October 24, 2026.
| Parameter | FastR | Log Dyno |
|---|---|---|
| Price | Free — better | $13.99 |
| Rating | 4.4 (319 ratings) — better | 3.4 (10 ratings) |
| Positive reviews | 37.5% of reviews — better | 15.4% of reviews |
| Number of ratings | 319 — better | 10 |
| Update frequency | Every 5 months | Every 4 months — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases — better | Paid |
| Devices | iPhone, iPod | iPhone, iPad, iPod — better |
| Requires iOS | 15.0 | 9.0 — better |
| Further details — not scored | ||
| Size | 20 MB | 128 MB |
| Age rating | 4+ | 4+ |
| Developer | Erhies Fekarurhobo | Adam Keninger |
Customer experience
FastR
Log Dyno
Bugs and requests
FastR
Reported bugs
10 issues- Network connection errors preventing vehicle selection
- Facebook login buffering and not connecting
- App fails to record and save acceleration times
- GPS speed readings lag significantly behind actual speed
- App crashes on launch or during use
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- Settings not saving properly without login
- Leaderboard functionality broken
- App doesn't start recording until vehicle is already at speed
- Inconsistent timing results on identical driving conditions
- Loading screen stuck on 'select vehicle' with persistent network errors
Requested features
10 requests- GPS-based auto-start feature instead of manual start button
- Audio cues for 'ready, set, go' countdown
- Alternative login methods beyond Facebook
- Save vehicle selection for future sessions
- Support for multiple vehicles per account
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- Social media sharing integration
- In-app instructions and user guide
- Add missing car models (Tesla Model Y, Russian models, high-spec variants)
- Allow custom vehicle entry if model not found
- Real-time sound feedback during acceleration test
Log Dyno
Not enough reviews yet to summarise bugs or requests.
In-app purchases
FastR
- 10 Leaderboard Posts$3.99
- Unlock 1/4 Mile Timing$5.99
Log Dyno
No in-app purchases









