Although the amount of malware when talking about mobile apps is not that big, Michael Sutton – VP of security research at Zscaler ThreatLabZ – is concerned about the mobile apps “that are sharing information that people aren’t aware of, or apps that have not been built securely” .
As an example he mentioned the apps that are requesting the passwords for Google Docs, and Dropbox, for the purpose to upload files and store backups. The credentials stored in those apps are not securely stored, usually as plain text, which is a BIG security risk.
All this happen, because the businesses are desperate to offer mobile apps for the masses and building them quickly usually leaves security holes. Just having an app downloaded from an official market doesn’t mean that those apps are securely built or that they have good systems that protect your privacy.