Even though we have installed WAB Dev on a server where multiple developers can access the site (so using the same installation directory and app code directory), the apps generated by one user are not visible to other developers. There is a link below where someone has submitted an idea to ESRI to make sharing possible, but I have yet to see an implementation in practice that works, other than transferring files around manually. As mentioned in that thread, it is common to have multiple developers working on the same project, needing to pick up where someone else left off, or just doing some testing.
If anyone has come up with a solution, any ideas would be greatly appreciated.
Share/edit Web AppBuilder code amongst a team.