A portable consumer device, such as a mobile phone or a tablet computer, may be configured to collect measurements data associated with at least one of movement of the portable consumer device or orientation of the portable consumer device, as well as data associated with an external environment of the portable consumer device. The collected data may be evaluated in order to determine motion of the portable consumer device over time and contextual information associated with the portable consumer device. A user activity may be determined based upon the determined motion and the determined contextual information. As desired, the user activity may be evaluated in association with a suitable application scenario, such as a gaming application scenario.