This is a good startup idea. I used to work at a company that heavily misapplied Scrum[1], and they bent over backwards to spend as much money as possible on anything that said "Scrum" on it. Software, consultants, everything. Basically, this should be easy money for you :) The people doing Scrum right will also be happy to pay for software that makes it easier.
[1] (I loved the misapplication of Scrum. The Scrum book we were using had examples of things to never do, and that's exactly what we did. We actually had 8-hour sprint planning meetings every two weeks, in addition to an 8-hour "demo days" and "retrospectives"... leaving 7 days out of every 10 for actual work. Of course, those were cut into by other meetings like "architecture working sessions" and so on. In the end, nobody got anything done, so they added even more meetings to determine why that was the case. Around that point, I quit.)