Use either of 2 performance modes to seamlessly switch up patches and effects during live shows. PRESELECT mode lets you jump from patch to patch without affecting your current sound, while STOMP mode lets you turn individual effects on and off.
I've played guitar for a while, but only just started learning the bass, and the Zoom B1 Four has been invaluable to my progress.
Not only does it have a great range of sounds and effects that you can customise to further inspire your playing but it has rhythm tracks and a looper to help you practice riffs and bass lines over and over to perfection.
For the price, you can't beat it.