getUniqueId

Get a unique alphanumeric device identified.

The returned identified might not be truly unique if the device does not offer one; in any case some identified is always returned.

The unique identifier is limited to 16 alphanumeric characters.

The identifier is the first one available of the following:

1. IMEI
2. serial number prefixed with “S”
3. Adroid ID prefixed with “A”
4. model code prefixed with “M” (this is the not really unique but at least something is returned)

If the real source is too long, a hash is used instead.