Harry's Dyno

Content rating
Everyone
1K+
Downloads
Content rating
Everyone
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About this app

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/android

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
Harry's Dyno is your high precision performance measuring app.
Updated on
Jun 28, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • No data shared with third parties
    Learn more about how developers declare sharing
  • This app may collect these data types
    Personal info, Messages and 2 others
  • Data isn’t encrypted
  • Data can’t be deleted

What’s new

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

Sensor support
- added support for Haze GNSS
- added OBD support for Hybrid battery SoC plus tank gadget
- 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