Android several APIs to store application data in or databases. Every application possesses a separate
data directory to store this data. To ensure access con-
trol on these , Android makes use of the traditional access control mechanisms deployed in Linux systems using
the unique user and group identier to an appli-
cation. To exchange data with other applications, Android
applications must content providers (see Section 2.1).
Access rights to these providers are statically in the
manifest. Another option to share data are intents. As explained above, access to these messages must also be dened
in the applications' manifest.