Microsoft Skype can be used for study groups or one-on-one tutoring. It works on most cell phones and computers.
It is more convenient than other conference tools for some things, like sharing vision of a computer desktop or group video calls.
On at least one occasion, an in person meetup was replaced with a skype group call because of an inclement weather event
https://www.skype.com, or search Play store or your favorite app store.
You will need to create an account or use an existing microsoft account.
Some board games can be played over skype,
Please practice muting and unmuting your microphone, and turning on and off your video.