http://forum.xda-developers.com/showthread.php?p=6518838 If you push it to /data/app you can uninstall the app from the phone (Settings>Apps>Manage Apps, or 3rd party apps). If you push it to /system/app you can only uninstall via ADB or terminal on the phone (there might be an app on the market be able to remove it also). That's really the only difference I see. 另外有人說Android Market update之後,還是會被放在/data/app目錄