A flexible electronic device is made up of nanostructures. Specifically, the device includes a flexible substrate, a film of nanostructures in contact with the flexible substrate, a first conducting element in contact with the film of nanostructures, and a second conducting element in contact with the film of nanostructures. The nanostructures may comprise nanotubes, such as carbon nanotubes disposed along the flexible substrate, such as an organic or polymer substrate. The first and second conductive elements may serve as electrical terminals, or as a source and drain. In addition, the electronic device may include a gate electrode that is in proximity to the nanotubes and not in electrical contact with the nanotubes. In this configuration, the device can operate as a transistor or a FET. The device may also be operated in a resistive mode as a chemical sensor (e.g., for sensing NH3).