You can change the display name for your Spark 4K devices to more easily identify them in the Launchpad App. For example, you can rename a transmitter to “Tx 4” and rename its paired receiver to “Rx 4” for easy reference.
Power on the devices you wish to unpair and make sure bluetooth is enabled on the devices via the small button on the back.
Then in the status page, tap the three dots in the upper right to enter Settings. Then tap on TX/RX OSD Name.
In the Name page, tap the field and enter your desired name. Tap Apply to save your changes. Your device will now be renamed.