An infrared blaster (IR blaster) is a device that relays commands from a remote control to one or more devices that require infra-red remote control. For instance, it may also allow radio-frequency-based (RF) remotes (including those using Bluetooth) to control infra-red-based components. It may also allow one device to control another: A recording device, such as a DVR or VCR, might change the channel on an external tuner (such as a cable box or satellite television receiver). This way, the receiving device can automatically be set to the correct channel before the recording process starts. An IR blaster can be used to implement remote control of components from a mobile phone, tablet, or computer.