A board with stickies is the best idea for bringing a team together and seeing your work in progress. You might decide that you need to see your flow, too, which an electronic board will not let you see.
I never recommend to a team that they start with an electronic tool. I always recommend that they start with cards or stickies on a physical board. Otherwise, the tool dictates the process. You want the team to learn the process and learn how to bea team.