Celem artykułu jest porównanie cech API dla najpopularniejszych platform programistyczno-systemowych zaawansowanych telefonów komórkowych, tzn. platformy Java Micro Edition, Android oraz nowego systemu Windows Phone 7. W części praktycznej przedstawiono parametry i wyniki pomiarów uzyskanych poprzez opisywane API akcelerometrów wbudowanych w telefony Nokia 5800 XprcssMusic i LG GT540 Swift. Jak wykazano największe możliwości posiada obecnie platforma Java ME jednak szybko rozwijające się systemy Android i Windows Phone 7 mogą tą sytuację szybko zmienić ponieważ posiadają unikalne funkcje wykorzystujące kilka czujników jednocześnie.%The aim of this paper is a comparison of API capabilities for the most popular system-programming platforms of cellular phones (Smartphones), i.e. Java Micro Edition platform, Android system and new Windows Phone 7 system. Section 2 contains an introduction to terms of an accelerometcr and phone axis of acceleration measurement. Sections 3, 4 and 5 are descriptions of programming library members for sensor services of Java ME, Android and Windows Fhone 7 platforms. Parameters of internal accelerometers for Nokia 5800 XpressMusic and LG GT540 Swift phones are given in Section 6. There are presented the results of measuring the Earth acceleration along all three phone axis. Information of accelerometers and acceleration values were read thanks to utilisation of API functions described before. They are Mobile Sensor API of Java ME for Nokia and Android system API in case of LG phone. As it is shown in Tab. 1 the measurement accuracy as well as the values of acceleration measured along particular axes are different for the tested devices. The maximum error reaches 7%. As it is shown all programming interfaces allow reading data asynchronously. Java ME platform has got the largest range of functions and supported kinds of sensors but fast developing Android and Windows Phone 7 systems may change this situation quickly. They have got some unique abilities, e.g. functions which use data from multiple sensors during attitude measurement.
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