# Harry's Dyno

> High-precision GPS and OBD-based vehicle performance measurement app. (iPhone/iPad app by Harald Schlangmann.)

- Source: https://appshunter.io/ios/app/harrys-dyno/id1148400332 (this page in markdown: same URL + `.md`)
- Developer: [Harald Schlangmann](https://appshunter.io/developer/307688601)
- Category: Sports, Travel
- Price: $3.99
- Rating: 1.00/5 from 2 App Store ratings · 4 written reviews indexed
- Age rating: 4+
- Requires: iOS 12.0 · 41 MB
- Languages: American English, French (France), German (Germany), Italian, Japanese, Chinese (Simplified, China), European Spanish, Chinese (Traditional, Taiwan)
- Released: 2016-09-26
- Data updated: 2026-08-20
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/harrys-dyno/id1148400332/reviews.md

## What is Harry's Dyno?

Harry's Dyno is a high precision performance measuring app. It utilizes GPS and OBD sensor input to recognize arbitrary speed ranges like 0-60 mph or 100-200 km/h. Both acceleration and deceleration testing is supported.

Results can be compared and analyzed in details. Using two-cursor mode, one can inspect subranges of data recorded (e.g. 80 to 120 km/h for a 0 to 200 km/h). Data is stored locally and can be filtered by speed range and vehicle used. It can be exported to various data formats too.

Provided the smartphone is mounted in a position with good GPS accuracy, the internal GPS can be used for measurements. For short speed ranges, high powered vehicles, and highest precision, either external GPS or OBD sensors can be connected. OBD adapters are actually preferable as speed changes are available instantly. We have an always up to date list of compatible accessories available here: www.gps-laptimer.de/compatibility/ios

For distance based performance testing (quarter mile etc), please use Harry's LapTimer currently. This mode will be added to Harry's Dyno as a free upgrade shortly.

For Harry's LapTimer users! Harry's LapTimer GrandPrix has received a free feature upgrade and includes Harry's Dyno functionality now: please follow LapTimer ‣ Race ‣ Performance to use the dyno mode. In case you have used Harry's LapTimer Petrolhead so far, you may either upgrade it to GrandPrix (LapTimer ‣ Administration ‣ Add-ons), or go for Harry's Dyno as a separate app.

Enjoy and let us know what you think! For questions, tipps & tricks, and support, please use our forum www.gps-laptimer-forum.de

## Key features

- GPS and OBD sensor integration
- Custom speed range testing (acceleration/deceleration)
- Detailed results analysis
- Two-cursor data inspection
- Local data storage and filtering
- Data export to various formats

## Recent user reviews (4 of 4)

All indexed reviews: https://appshunter.io/ios/app/harrys-dyno/id1148400332/reviews.md

### 1/5 — Crashes on startup

*2022-01-07*

This needs to get fixed. The app is rendered completely non functional.

### 1/5 — Crashes immediately everytime

*2020-06-01*

After the last update. The app crashes everytime immediately upon opening. This is on a ipad 7. So not like it's because it's on a outdated ipad.

### 1/5 — Don’t bother.

*2018-11-14*

Basically doesn’t work, won’t measure acceleration.

### 1/5 — Doesn't work

*2016-11-23*

It doesn't work propperly on my iphone 7, it's too slow to achieve the speed...

## Frequently asked questions about Harry's Dyno

### What is Harry's Dyno used for?

Harry's Dyno is a high-precision app for measuring vehicle performance. It uses GPS and OBD sensor input to test acceleration and deceleration across custom speed ranges, allowing for detailed analysis of results.

### Does Harry's Dyno support external sensors?

Yes, for short speed ranges, high-powered vehicles, and the highest precision, external GPS or OBD sensors can be connected. OBD adapters are preferable as they provide instant speed changes.

### How can I analyze the data in Harry's Dyno?

Results can be compared and analyzed in detail. The app features a two-cursor mode for inspecting subranges of recorded data, such as 80 to 120 km/h within a 0 to 200 km/h test.

### Can I save and export my performance data?

Data is stored locally and can be filtered by speed range and vehicle used. The app also allows data to be exported to various formats for further analysis or sharing.

### What is the price of Harry's Dyno?

Harry's Dyno is a paid application, priced at $3.99. This one-time purchase grants access to its full performance measuring capabilities.

### Is Harry's Dyno suitable for all ages?

The app has an age rating of 4+, indicating it is generally suitable for younger users. However, its primary functionality is for adult vehicle enthusiasts.

### How often is Harry's Dyno updated?

The app was last updated on May 6, 2025, with version 25.0.0. This indicates active development and regular updates to improve functionality and compatibility.

### Does Harry's Dyno have ads?

No, Harry's Dyno does not contain advertisements. As a paid application, it offers an ad-free experience for its users.

## Version history (last 5 releases)

### 25.1.0 — 2026-06-24

User Interface
- added option to scroll buttons in case available buttons do not fit screen width

Sensor support
- added support for Haze GNSS sensors
- added OBD support for Hybrid battery SoC plus tank gadget allowing to toggle between tank and battery level
- added heading support for NMEA sensors w/o RMC (like Columbus)
- fixed a scripting error in RaceboxMini sensor implementation
- made hundreds seconds handling for Racebox Mini more robust
- fixed a bug in CSV headers

### 25.0.0 — 2025-05-06

- reimplemented support for RaceBox Mini, Mini S and added RaceBox Micro
- added support for RTK GNSS sensors
- added support for Columbus P-70 Ultra sensor
- change accuracy precision to centimeters / inches
- added support for NetRTK / NTRIP casters
- completely new and full localizations for Japanese, Chinese (traditional, simplified), Spanisch, French, Italian
- made NMEA parser more resilient to changing sentence pattern
- updated list of iPad/iPhone models (M4 iPad, iPhone 16)
- fixed a bug in day / night weather icons
- fixed a problem that positioned forward / backward buttons wrongly in Lap Details
- fixed order of parameters in Sensor Configuration dialogs 
- improved BTLE write operations
- improved NMEA sentence displays
- dozens of minor fixes, improvements, features

### 24.9.1 — 2024-06-30

- reworked routines checking available storage
- use expert setting "Low Memory" to remove all storage checkings

### 24.9.0 — 2024-05-05

- fixed a bug in gear calculation
- replaced deprecated acceleration framework
- added support for Vgate vLinker FD+/MC+/BM+ OBD adapters
- fixed and improved VBO import
- rechecked Racebox integration to deliver high update rates

### 24.8.2 — 2023-06-29

- Added support for Racebox Mini S
- Added an Expert Setting to adjust the number of minutes recent fixes are displayed in Map View

## Apps similar to Harry's Dyno

| App | Rating | Price | Category |
| --- | --- | --- | --- |
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| [Race Buddy: Lap & Drag Timer](https://appshunter.io/ios/app/race-buddy-lap-and-drag-timer/id1440030429) | 3.6 (11) | Free | Sports |
| [Test-Drive: Drag car 0-60 mph](https://appshunter.io/ios/app/test-drive-drag-car-0-60-mph/id1403831794) | 2.7 (3) | $10.99 | Sports |
| [R-EX](https://appshunter.io/ios/app/r-ex/id1620549211) | — | Free | Sports |
| [RaceChrono Pro](https://appshunter.io/ios/app/racechrono-pro/id1129429340) | 4.7 (174) | $19.99 | Sports |
| [Dexian Timer](https://appshunter.io/ios/app/dexian-timer/id6759848554) | — | Free | Sports |

## More apps by Harald Schlangmann

- [Harry's LapTimer Rookie](https://appshunter.io/ios/app/harrys-laptimer-rookie/id307688598)
- [Harry's Sailor](https://appshunter.io/ios/app/harrys-sailor/id319244049)
- [Harry's GPS/OBD Buddy](https://appshunter.io/ios/app/harrys-gpsobd-buddy/id320423931)
- [Harry's LapTimer Petrolhead](https://appshunter.io/ios/app/harrys-laptimer-petrolhead/id338257907)
- [Harry's LapTimer Grand Prix](https://appshunter.io/ios/app/harrys-laptimer-grand-prix/id363556704)
- [Harry's Camper](https://appshunter.io/ios/app/harrys-camper/id952167017)

All apps by Harald Schlangmann: https://appshunter.io/developer/307688601

## Related topics

[dyno nobel](https://appshunter.io/ios/topics/dyno-nobel) · [dyno car](https://appshunter.io/ios/topics/dyno-car)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-20.*