A functional library can secure data gathering devices of a personal computing device on behalf of a secure application program to provide a more secure computing session during which sensitive data gathering activities are performed using any of those data gathering devices. The functional library, when incorporated within a personal computing device, creates a secure personal computing device on which to execute application programs such as mobile banking applications. The secure functional library acquires exclusive access to one or more of a predetermined plurality of the data gathering devices on behalf of a calling secure software application. Exclusive access is achieved by gaining access to each of the predetermined set and then locking that access throughout either the entire computing session, or at least until the execution of sensitive data gathering activities being performed during that computing session have been completed. The data gathering devices to be included in the predetermined set can be those that are deemed particularly vulnerable to exploitation in view of the types of sensitive data gathering activities to be conducted, or simply all of them for maximum security. The predetermined set can be defined and set for a particular application, or they can be defined more generally within the context of specific sensitive tasks or activities to be conducted.