PhoneSat is an ongoing NASA project of building nanosatellites using unmodified consumer-grade off-the-shelf smartphones and Arduino platform and launching them into Low Earth Orbit. This project is part of NASA's Small Spacecraft Technology Program and was started in 2009 at NASA Ames Research Center.

A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under 1,200 kg (2,600 lb). While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites can be built small to reduce the large economic cost of launch vehicles and the costs associated with construction. Miniature satellites, especially in large numbers, may be more useful than fewer, larger ones for some purposes – for example, gathering of scientific data and radio relay. Technical challenges in the construction of small satellites may include the lack of sufficient power storage or of room for a propulsion system.