Should I use mobile or web?
Either! You can log in and find the exact same features and data (eg. your messages, sessions, etc.) across mobile or web. The mobile app has push notifications woven into the experience (reminders for sessions, chat, etc.) so we do recommend students get the app as well as using Penji on web.penjiapp.com.
What are different "communities"?
At many schools we work with, we support multiple tutoring or advising centers. These will have their own tutors and own modes of tutoring supported. You can switch communities in the side menu of the mobile app or the lower left of the web application.
What should I do to prepare for my session?
With tutoring, a little preparation will make the session MUCH more effective. Spend some time working on the problems or material before the session, and become quite clear about what step or what concept is really tripping you up. This work prepares your brain to learn those concepts quickly once you're with the tutor. Also be sure to share your materials with the tutor ahead of time so they can prepare.
How can I find a specific tutor I like?
The first step in Penji is selecting a time, after which you can pick a tutor who's available at that time. If you don't see the tutor you're looking for, check another time or two and you'll find them. You can also chat with them to ask when they're free. Usually, tutors have a recurring weekly schedule, so you'll learn pretty quickly the windows they are tutoring.