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1、第18页AnAnalysisandComparisonofOpenandClosedMobilePlatformsAndroidvs.iPhone1.IntroductionInrecentyears,thepopularityofsmartphonekeptgoingup.Moreandmoresmartphonesaresoldandalotofpeopleareembracingthem.Smartphonesbroughtgreatconveniencetousers,aswellcreatedopportunitie
2、sforsmartphoneresearchers.That’stosay,thewidespreadofsmartphonesbenefitedbothsides.Atthesametime,developingofsmartphoneOSbecomesoneofthesmartestindustry.TobeasmartphoneOS,thesystemshould:1.ProvideserviceslikeaPC.2.WorkwithaGPUforbettervisualeffects.3.Allowtheusertos
3、urfonInternetfreely.Andapparently,there’realsosomeweaknesses:1.Limitedbattery.2.PoorCPUperformanceagainstPCCPU.3.Smallstorage.4.TheuseofRAMmayleadstolossofdatawhenthephonerunsoutofbatteryNowthe2giantsofsmartphoneOSareAndroidandiPhoneOS.Ononeside,AndroidisbasedonLinu
4、xkernelandDalvikvirtualmachine,anditisopensourced.TheupperlayerofAndroidisJavabased,allowingdeveloperstodevelopAndroidapplicationswithGoogleSDKandselltheirsoftwareinAndroidMarket.Ontheotherside,iPhoneOS,whichbasesonUnixkernelandDarwinmodelbutisclosedsourced,evolvesf
5、romMacOSXandisthedefaultOSofiPhone,iPodTouchandiPad.ObjectiveCbasedsoftwarecanruniniPhoneOS,andjustlikeAndroid,youcandevelopyourowniPhoneapplicationsanduploadthemontoApple’s‘AppStore’forsale.BycomparingthelatestAndroidandiPhoneOS,Android2.2FroyoandiOS4,wecantakeagli
6、mpseatthemainfeatureofopenandclosedsmartphoneOSs.Whilethe2OSsaredesignedinratherdifferentmentalityandfunctionality,it’salittleearlytotellwhichoneisbetter.2.SmartPhoneOS2.1.Android第18页ThesystemarchitectureofAndroidconsistsof5layers,whichareLinuxKernel,AndroidRuntime,
7、Libraries,ApplicationFrameworkandApplications,frombottomtotop.Androidprovidescoreserviceslikesecurity,memorymanagement,processmanagement,networkstackanddrivers,basingonLinux2.6.Beingtheabstractlayerbetweensoftwareandhardware,thelayerofLinuxKernelhidestheimplementing
8、detailsofhardwareandprovidesintegratedservicesforupperlayer.DalvikvirtualmachineandJavacorelibrariesareincludedinthelayerofAndroidRuntime,