1. A method to generate a true random number for use in a cryptographic operation, the method operative in a mobile device comprising an operating system, and one or more hardware devices, comprising: pooling into a data store entropy data generated from the one or more hardware devices to form an entropy data pool; responsive to a request, retrieving entropy data from particular locations in the data store; using the entropy data retrieved to generate a true random number; and clearing the particular locations from which the entropy data was retrieved.