Who are the people who wants to protect their data on their Pocket PC?
What are their job industry?How old are they?

Well, I'd say everybody wants to protect their own personal data.
Different people in different industries might have different needs,
so it's impossible to make one sweeping generalization about who does
and who does not want to protect their own information.

For example, people in computer security may manage a list of hundreds
of passwords that they have to keep track of. They would require
strong encryption before they'd be willing to write this information
down. Others may need to protect financial information like bank
account numbers. Perhaps a user has some company secrets they need to
transport--that would be a user for encryption as well. The users of
this sort of technology are far and wide.

Hi, Sorry you question is too generic. Probably everyone who wants to
carry some data with him/her and do not want somebody else to get
access to it in case device gets stolen/lost.
examples: passwords, sensative documents, etc. 
Protection: encrypt data or lock device
soft: 1-Pass (omegaone.com) would lock your device - very easy to use
allows using buttons as pass. or eWallet - encrypt data in the file
(password, credit cards info, etc.)

Hope this helps. 

:)