Even the technical challenges are significant. It's one thing to make an app, it's another thing to have a 24/7, global, distributed application with lots of m

Even the technical challenges are significant. It's one thing to make an app, it's another thing to have a 24/7, global, distributed application with lots of money running through it. You'll need site-reliability teams to handle maintenance issues and a significant number of developers on staff. If there's some new law, regulation, or bug which requires changes to your system it needs to be done NOW, not whenever someone gets around to it. >who handles crimes like assault or theft between the various parties? who sets up payments and issues refunds? Lawyers. You're going to need a lot of lawyers.