For those looking for a quiz/test tool, classmarker might be one that you could try out. I've used classmarker for about 5 years now, and I really like the many options it has. The ability to make question banks quite easily, and re-use quizzes/tests over and over again for different groups makes it really nice if you are teaching the same classes again and again. It can be a bit complex with all the different settings/tools/options/etc. but I think you will find it useful and easy to use if you are looking for a powerful quizzing/testing tool.

Remind is a tool used to sent students or parents quick updates or reminders to their cell-phones via text (or to email). It allows teachers/facilitators to organize their classes into groups, and send messages without either party ever having to share their phone numbers with the other, therefore limiting privacy concerns. Instructors are able to have different classes or groups, which allows specific communication with individual groups, or even parent groups. Facilitators can also schedule reminders/messages to send on a future date and time, which allows seamless flexibility in when you want to send your reminders. It's a tool use regularly with my f2f classes, and the feedback is extreamly positive.