We haven't implemented a conversational UI yet. Messages are currently one-way. We'll be adding in voice support soon too so that you can call in and hear your schedule (even if you just hang up after when your "next shift" is).
As we roll out two-way messages, I've been contemplating internationalization. Date formats are somewhat universal, but for things like shift swapping - I think that we could overcome a lot of usability issues by adding Spanish support quickly.
Regarding cost and education - we also learned in user tests that we still need to support a print schedule. We're in the process of building that out. Our focus is on making structured, accurate scheduling data available to other systems (such as payroll). If that means that we need to focus on a printable view, that's fine :-)