When I was in university we had that peculiar professor for Quantum Mech. He would let you choose any question sheet and use books to consult. And after you say

When I was in university we had that peculiar professor for Quantum Mech. He would let you choose any question sheet and use books to consult. And after you say you are ready he would briefly look at your answers and will fry your brain with the questions till you are dead. Usually all my university exams were 4s and 5s out of 5. I got 3 on quantum mech and considered myself extremely happy. Drank myself to death after that. Many of the people would be just told go home, study and return some other time. Phew. No gadget will save you from examiner like that one.