Yes, you may use a mobile device for a session but it is not recommended practice.
The online classroom has a lot of possibilities that can't fit nicely into a small screen such as that of your mobile device.
If the lesson is a listen to only, then sure, go ahead. Still, we don't advise this.
After all, you can do a test by going to an online classroom on your own and checking how it looks on your mobile phone. If you feel confident in the success of the lesson and the knowledge you'll receive, feel free to use your mobile device for a session.
For any further questions or inquiries, contact us at 855-661-3688.