On Android devices, the application itself and cached content are stored on internal storage. Internal storage on Android devices is always secure (unless the device has been rooted contrary to manufacturer recommendations). iOS devices do not have a concept of external storage, so data within the application is always secure.
Files that are downloaded or opened in third-party apps are by nature less secure than files that remain within the app. On Android devices, downloaded files are stored on the device’s external storage.
It is up to you as the Filr administrator to decide whether to allow users to download files and open them in third-party applications, as described in Section 13.1, Configuring Mobile Device Access for All Users.
In order for downloaded files to remain secure, users should configure their devices to encrypt files. However, not all devices support file encryption. For information about how to enable file encryption on iOS and Android devices, see Encrypting Downloaded Files
in the Novell Filr Mobile App Quick Start.