(THIS CODING RULE OR GUIDELINE IS UNDER CONSTRUCTION)

In Android apps, data can be communicated via intents, or data can be written to files, distributed using shared preferences, or stored in databases.  In all these cases, if the data is sensitive, it is important to keep the data secure.  That is, it should not be possible for other apps (or, more strictly, apps with different userids) to be able to access this data, or for the data to be accessible to other programs or people, if the data owner does not intend that. 

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