I just have a few comments on your poll, for your first option, I don't know how exactly this is going to work, because usually tutors are the ones accommodating the student's learning style and all tutors should have a significant capability in their respective subjects to tutor it, so I am not sure whether this will even work, as for your second option, many tutors find it easier to organise their own students into small classes, and considering usually one tutor don't tutor a significant amount of students, not sure whether it won't be easier for the tutor to arrange it themselves, not sure whether you need an entire website for it. For the third option, many tutors already offers online essay marking services, including those on boredofstudies, so once again not sure how much of an interest you are going to generate, and there are competing websites offering similar services as well, so you will need to think of significant strategies to differentiate yourself and your competitors. For your fifth one, once again, often tutors already do these things very easily with their laptop and mobile phones, not sure whether it is worth the cost and time to make a tutoring app when the current basic systems tutor use to communicate with their students is already very convenient, and lastly, there are quite a few websites that already allow tutors to sell original study materials, so once again not sure whether it is economically viable to develop an app for it and whether you will have enough resources to promote the app to ensure enough users are utilising it. Overall, I think you need to develop more detailed strategies or differentiate your service from existing competitors in some way in order for your idea to be viable and profitable.