This clip-on tuner is chromatic which means it has every note available, unlike a guitar tuner. We have looked at many tuners, and this simple one is a good price and does the job well. It is easy to use, with a back light that is white but turns green when the note is right. It clips on to either the calabash at the sound hole, the neck or the bridge.
Although it does use contact with the kora to determine the pitch rather than a microphone (a piezo type), it is not really suitable for performers trying to tune in a noisy environment.