1. A computer-implemented method for recommending one or more tasks to a crowdworker, the one or more tasks are selected from a plurality of tasks offered by a plurality of crowdsourcing platforms, the computer-implemented method comprising: identifying one or more categories associated with the plurality of tasks offered by the plurality of crowdsourcing platforms; determining, at a login time, values of one or more utility parameters of the crowdworker corresponding to the one or more categories; selecting the one or more tasks from the plurality of tasks by choosing one or more constraints on the determined values of the one or more utility parameters of the crowdworker; and recommending, at the login time to the crowdworker, the one or more tasks associated with the crowdworker based on selecting.