In Android's filesystem encryption do they also encrypt the SDcard? If so Is encrypting the SDcard optional or is it encrypted by default when you choose to encrypt your device?
Android provides the capability to do filesystem encryption, but it's up to the vendor who builds the firmware for your device to enable it for the SD card. I have only seen a few devices with this capability enabled for the SD card, though most seem to have it for the internal storage (
Here's the option for the Galaxy Tab 2 for example:
The encryption of the SD card is a device-specific subject, but as far as Android goes, only
Android default behaviour:
By "default", for Android, the encryption on the device is applied to
See: Apps on SD Card: The Details scroll down to the below paragraph
Android recommendation to developers:
See: Designing for Security scroll down to the below paragraph
Why Android, why?
Android believes that external storage is a shared thing, so, to be accessible everywhere, being encrypted wouldn't work.
Some vendors "act on their own"
Some vendors like Motorola however have implemented the encryption to