Why do people use this kind of tuner? It’s quick and it’s accurate. You could sit there for hours using one of the guitar tuners that you plug in with a basic guitar cable, and that would work well enough, but the advantage here is speed. So when you’re in the middle of playing a show, and a string breaks, it’s easier to clip on a tuner that will go by vibration than it is to unplug your guitar, turn off the amp, and sit there for an hour to re-tune your whole instrument. In addition, I know I keep saying that this is the “best guitar tuner” but it works well for other instruments too.
So, if you happen to be in an Irish Folk Metal band, and you have a female violin player who happens to be a better musician than everyone else in the band, but she keeps getting out of tune because she’s rough on her instrument, this is the tuner you need. It’s the kind of tuner that the guitar player, bass player, violinist, and mandolin player can all use, and it’s small so you can pass it around. That’s the other big advantage, size. I have one of those bigger tuners that you actually have to plug in, yet I still use my bass player’s (which happens to be this exact tuner) mainly because of size and convenience.