Mems-based flow systems in waterproof devices

A method, comprising:

• driving at least one cooling element of an active cooling system to undergo vibrational motion;
• wherein the active cooling system is in a smart phone including the active cooling system, a housing having a plurality of apertures therein, and at least one of a plurality of membranes or a plurality of valves coupled with the plurality of apertures, each of the plurality of membranes being watertight and gas breathable, the plurality of valves being configured to prevent entry of water through the plurality of apertures, when activated the vibrational motion of the at least one cooling element driving a gas through a membrane of the plurality of membranes but not driving the water through the membrane.