Без ведома пользователя - нереально. Но можно запустить uninstall.
"A 3rd party app cannot install or uninstall any other packages programmatically, that would be a security risk for Android. However a 3rd party app can ask the Android OS to install or uninstall a package using intents" (с)
"Note that even using reflection or other tricks to access installPackage() will not help, because only system applications can use it. (This is because it is the low-level install mechanism, after the permissions have been approved by the user, so it is not safe for regular applications to have access to.)"(с)