Babble_17,

On the mobile devices the SmartStore technology, provided by the Salesforce Mobile SDK, is used to house the data. In essence SmartStore uses SQLCipher with AES256 bit encryption.

Data is transferred directly between the device and Salesforce over https, no middle server architecture is in place.

Hi Terrier01,

Our full device and OS policy can be found here.

At the time of writing we support back to Android 4.4

Just for info - restrictions on devices/OS are applied by various factors including lower-level support of the Salesforce Mobile SDK.