[Flounder] Smart-phone security

[DL Neil]

What level of security does a smart-phone possess that my computer does not?

Responding to my protest that Internet Banking (using PC) could not 
carry-out functions that are available on 'the app' (using smart-phone), 
a teller at my bank (kindly) informed me that it was because a 
greater-level of security was possible using the latter.

True or False?
What security facilities are available on a smart-phone that cannot be 
reproduced on a (Linux?Windows?Mac) PC?

-- 
Regards =dn