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"When you grow up in Germany, you dream of Porsches.  On track, any GT3 is what you want."


Harry’s Laptimer:  Q and A with Harald Schlangmann

by Ziva Allen


Harald Schlangmann is a computer scientist who lives in Cologne, Germany, not far from the Nordschliefe, otherwise known as the Nurburgring. Harryslaptimerc Harald frequently drives that awesome almost 13 mile track in his Porsche.  Harald started dabbling in computers when he was 14 and then went on to earn his Master’s Degree in computer science.  He worked for IBM in Germany for 16 years, rising to the level of Vice President.  During his last six years at IBM, Harald began a small IT company to develop Harry’s Laptimer.  Harald points out that this is not really a job for him, but a hobby.  It was as a result of his wanting something to time his laps on the Nordschliefe/Nurburgring that Harald gradually began creating the technology behind his application. This work combined his two interests; technology and high performance driving.  There was another coming together that is part of the story of the development of Harry’s Laptimer.  According to Harald, the iPhone 3’s technology, the advent of external GPS sensors, and the ability to connect to the internet wirelessly via satellite made in-car data logging from a cell phone possible.  The biggest technological advance has been in combining video capture with data logging and overlays.  Harald is currently working towards integrating additional external cameras and developing an Android version.  Harald says of his work, “It is more of a passion and a dedication than an economically driven activity.”



Q.  Tell us about your history as a high performance driving enthusiast.



A.  I started track driving with a slightly tuned street motorbike; an Aprilia SL1000.  I live near Nürburgring, so it is easy to run some laps at weekends.  Driving the Green Hell with a bike has been great fun but extremely dangerous. After a few years (and a crash), I switched to cars.


Q.  Which cars have you driven as track cars?


A.  Mostly Porsches, plus a BMW and a Subaru.


Q.  Which models in particular?


A.  In time order the BMW 530i, Subaru Impreza WRX, Porsche 911 GT3 (996), Porsche 911 Carrera (997), Porsche 911 Carrera GTS (997).


Q.  Which tracks have you driven?  Nurburgring?


A.  I have driven at Nürburgring GP, Nordschleife, Sachsenring, Spa-Francorchamps, Zandvoort, as well as several autocross courses and training centers.


Q.  Have you also raced? 


A.  No, never.  I’m a big fan of spending time on things I have talent for and am really competitive at.  I consider myself to be a good and fast driver, but mainly because I’m very strong in analytics and understanding of driving physics and not because I’m extremely sensible or gifted with over-average strong reflexes.  I doubt I would make it to the top 20% in racing, but I’m sure I’m in the upper 2% of programmers.  So I drive for fun and as often as possible, but spend a lot more time on LapTimer (which is a passion and not work for me).



Q.  What modifications have you done to your cars?


A.  Chip tuning only, nothing special.


Q.  Do you do your own mechanical work on your cars?


A.  During my time at college, keeping my 34 PS Renault 4 running.


Q.  Which cars do you own now?


A.  A 2011 911 GTS, and a 2013 Land Rover Defender.


Q.  Which are the greatest cars you have driven and why?


A.  When you grow up in Germany, you dream of Porsches.  On track, any GT3 is what you want.


Q.  Which are the greatest tracks you have driven and why?


A.  I like them all.  Each one has its attractions and unique challenges.


Q.  Tell us what it is like to drive the Nordschleife.


Harryslaptimercar320x209cA.  The Nordschleife is certainly completely different to what you will drive elsewhere. It is   difficult to learn as you have so many corners to memorize, pavement is changing all the time, you need to be pretty brave when you drive it fast (no view behind the corners and hills, low security standards in general). In comparison, modern GP tracks are pretty boring.


Q.  How have you used technology to enhance your driving skills?


A.  As I have never had a dedicated track car, I never did a lot of tuning or hardware modifications.  Even the slowest car is fun when driven at its limit.  You can make your car faster by focusing on your driving skills.


Q.  What is the role of data in improving as a driver?


A.  It is huge.  Especially when getting some guidance on how to read data.  Analyzing the impact of different lines driven, checking your braking behavior, eliminating times without throttle and without brakes (coasting), and analyzing your “brake into the corner” behavior will make you a lot faster.


Q.  What led you to develop Harry's Laptimer?


A.  The original LapTimer dates back quite some time.  The initial programming took place in 2004/2005 on the PalmOS platform.  The first public release was on 14th of March 2006.  It was designated version number 1.6 and targeted Palm devices (at this time, the Treo650 and Tungsten devices).  The app was developed for my own requirements, wanting something to time laps on the Nordschleife.  This is the reason for the name “Harry's LapTimer” and the reason the initial public release was 1.6 and not 1.0.


Q.  What are the key features of your application?


A.  It is simply the most powerful lap timer and data recorder available today.  As a smartphone app, it is extremely inexpensive too.  Here are some of its key features: a) it records full high definition video in the background and allows overlaying and viewing on site; b) with its broad support for external sensors, it can be expanded using external sensors including up to 20 Hz GPS and 10 Hz OBD; c) it is easy to use, powerful, and beautiful; d) due to the hardware developments in the smart phone arena, LapTimer allows features that classic loggers cannot compete with.  As an example, you can post a fast lap just driven to Harry’s LapTimer server; other drivers can download and learn from it immediately.


harryslaptimerlogocQ.  What are you working on now?


A.  The good news is LapTimer evolves all the time.  I have a long list of additional features proposed by LapTimer users.  As long as the demand is high, I will invest time in these features.  Existing LapTimer users have been benefiting from this for years already.  In addition, I run several projects with automotive companies.


Q.  What features do LapTimer users ask for?


A.  Additional external cams to integrate, performance testing, vehicle database, race management, more real time information in the pits and for spectators, automatic crash    documentation, driver heart rate sensors, integration of specialized sensors, tons of small        improvements to handling and the user interface.


Q.  Petrolhead is the version of your lap timer that includes video with data logging.  When will Petrolhead be coming out for Android?


A.  Petrolhead for Android is in beta testing currently.  I have announced availability for the end of March and work on it day and night!



Since our interview with Harald, Petrolhead was released.  Harald provided us with an update and informed us that LapTimer seems to be the first app to create real overlays on the device (instead of showing some previews - which is a lot easier to accomplish).  Said Harry, "generating overlays on Android takes some time, but is very convenient as you do not need to fiddle around with several tools, transfer files, etc. It is just one button press and you are done. Petrolhead for Android is available here: and existing Rookie users upgrade from within the Rookie app."

I have not yet had an opportunity to check out Petrolhead, but planning on doing so soon. (Ed.)


Read our how to on video and data logging phone apps by clicking here.


Read our review of these apps by clicking here.



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