How important is location quality to users? By David Bartlett, Omnisense Ltd

David Bartlett, Omnisense Ltd, on quality, performance and the growing interest in location based services.


IMG_1721At the recent CW Location special interest group (L-SIG) meeting we addressed the question of position quality; how good is it really; how good might it be; and how does quality affect applications and users. There were some top quality presentations and some vibrant discussion ensued. You can find information about this event here:


What was striking was that the actual technical performance, and by this we usually imply accuracy but also latency, robustness, reliability etc., of positioning systems was never really in doubt. Most people were somewhat aware that they don’t always perform as well as claimed; that they have limitations; and that most vendors exaggerate their performance or omit to state under what conditions the performance will be achieved. No, a great deal of the discussion was about the applications and their interaction with us the users in a societal way. Whilst somewhat generational the lines are blurring and no longer can we simply split these opinions into young and old.


Shortly after the SIG meeting the app “Uber” was thrust into the limelight. Uber is an app that allows users to call a taxi; the app measures the time and distance travelled and takes payment directly from the user. The London cabbies are up-in-arms and suing Uber, though TfL has just ruled against them, declaring Uber legal The cabbies don’t object to competition, but they object to the fact that Uber uses a mobile phone as a meter, thereby, they claimed, circumventing the law that governs meters fitted in taxis for hire and bypassing their requirement to operate in a licensed regulated environment. The trouble is Uber users all over the world love the app: it provides them ready access to taxis at competitive prices and avoids the need to handle cash or haggle over charges. Of course, Uber is not the only such app, there are many others including Kabbee, Taxi Magic, Zipcar, Lyft, Easy taxi, car2go and others.


These apps are upsetting cabbies in London and many other places, but users love them. You can’t please everyone all the time, especially with disruptive technology and business models. However what happens when things go wrong?


Several years ago TfL conducted a series of detailed tests and analysis investigating whether GPS was suitable for use in road pricing applications (Results of one such test can be found here: Their conclusion was, broadly, not yet: even professionally installed systems in vehicles did not give good enough accuracy and reliability in urban areas and cities. So if GPS is not good enough (yet) for road pricing, is it good enough for metering a taxi journey? Especially using a hand held mobile phone, any android or iPhone, inside the vehicle? Uber has clearly put in place a mechanism for handling fare disputes: and there are several stories of bad fares circulating in the new media; but have the app developers properly understood the quality limitations of the positioning technology they’re relying on? Do users care or worry about this? Does it matter if the fare is 10% high or low due to errors in the mobile phone “meter”?


The reality is that as long as the user sees something that is plausible they simply accept what they’re told and don’t question it. If someone wanted to question it how would the average user go about validating positioning performance? So perhaps vendors of locating and positioning systems shouldn’t worry; as long as the result is plausible users will accept it and they either can’t or won’t check the accuracy of the result. But when things go wrong who do we blame: the positioning technology, the device (phone). the app, the user, the app vendor, the car driver or someone else?


About The Author

David Bartlett is CTO of Omnisense Ltd, and Co-Champion of the CW L-SIG
You can find him on LinkedIn:
Follow Omnisense on twitter: @iSenseOmni





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