With the introduction of Windows Mobile 6, Microsoft has taken a first step in closing the gap with BlackBerry for native device encryption (see table below for smartphone OS comparison). Windows Mobile 6 adds the ability to encrypt the entire contents of a memory expansion card. While this protects data stored on an expansion card (attachments, documents, etc.) in the event the card is lost or stolen, the contents of a device are still not encrypted. While more complicated than simply reading data off an SD card, reading the contents of a smartphone’s memory is not impossible.
Third party products are available that add device, file, or folder encryption to Symbian and Windows Mobile devices. In 2006, Juniper research forecasted the market for mobile phone encryption to reach over $1BB by 2011.
Comparison of Native Device Encryption by Smartphone Operating System
| RAM | Expansion (e.g. SD card) | |
| BlackBerry OS 4.1 | Supports | Supports |
| Symbian OS 9 | ||
| Windows Mobile 5 | ||
| Windows Mobile 6 | Supports |