Investigation of location capabilities of four different smartphones for LBS navigation applications

The market of smartphones and other mobile devices shows very high increase rates nowadays, e.g. the Apple's iOS-based smartphone and tablet series have gained 15% of global market share, while the Android-based smartphones and tablets have a share of 52.5% [11]. The intelligence contained in smartphones relies very much on the integration of different low-cost and compact sensors. MEMS-based accelerometers and magnetometers (or digital compasses) are integrated allowing manifold scenario-awareness applications (apps). Apple began this revolution by equipping the iPhone with an accelerometer to switch its display automatically from portrait to landscape orientation. Now Apple has a storeful of novel apps that exploit the iPhone's accelerometer for gaming, health monitoring, sports training and countless other uses thought up by legions of developers. It is forecasted that 85% of all smartphones by 2013 will include GPS, over 50% will have accelerometers and almost 50% will have gyroscopes [6]. Using these sensors smartphones offer location and navigation functionalities. Accelerometers can be used to determine the current movement state of the user, e.g. standing, walking, or fast moving in a car or public transportation. In addition, the digital compass can provide the orientation of movement. The research study discussed in this paper investigates the use of GPS and other geosensors for navigation applications. The conducted field tests cover combined indoor/outdoor environments in urban areas in the city of Vienna, Austria. In the tests the navigation capabilities of four different smartphones are investigated, namely an Apple iPhone 4, a Samsung Galaxy SII, a HTC EVO 3D and a Nokia X7. One main objective of the presented tests is to assess the quality of the data provided by the sensors in these smartphones. The test results show positioning accuracies on the few meter level using either GPS or dead reckoned positioning solutions with calibrated accelerometer and compass measurements. Therefore the feasibility of using smartphones for positioning in LBS and other navigation applications could be proven.