A radio frequency identification (RFID) device has controllable features that allow for modification of its interaction with external devices, such as RFID readers. The RFID device may have multiple antennas, coupled to multiple contacts of a chip of the device. The chip may include a real or virtual switch for selectively coupling the chip to either of the antennas. The switch may be activated by an external signal sent to the RFID device. The RFID device also may be controlled by adjusting an adjustable modulator within the RFID device. The modulator may adjust outgoing signals from the RFID device to an appropriate level of signal strength, or to have other suitable characteristics. By control of the antenna couplings and/or the modulator settings of the RFID device, adjustments in performance of the RFID device may be made for suitable operation in a variety of situations and environments.