Next month I will begin to learn in the university, and I am not sure if to buy smart pen such as Livescribe or Logitech IO 1/2 to write math with.(handwriting is not an option)
The problem is that I am not sure if these pens are comfortable, if they are easy to use and even if they are appropriate for math writing.
Are these pens really worth the price and appropriate for math writing?
When I occasionally go to e.g. Part III maths lectures or grad classes here in Cambridge, the students (a seriously smart bunch!) are almost all still using pen and paper. A very few use fancy tech in class, but that still seems very much a minority pursuit and not significantly increasing in propularity as the years go by (and remember, Cambridge students are typically not hard up: they can usually afford some pretty nifty hardware/software -- the place is awash with MacBook Airs ...).
I think there is a good reason why they are sticking with the basic old-school methods I picked up ... gulp! ... fifty years ago! Serious real-time first-pass note taking should quickly become second nature, and running annotations/corrections are so easy with pen and paper, not to mention mini-diagrams, arrows, comment boxes. Combine that if you like (and your lecturer is OK with it) with photos of the whiteboard at key stages. Some lecturers will distribute handouts -- again handwriting on them is a good way of taking additional notes.
And then after the class, the process of writing up revised notes as soon as you can -- now prettily LaTeXed if you like! -- gives you the all-important opportunity to think through and consolidate the material before the next class. Your mileage, of course, may vary: but this two-step process anecdotally still works best for most people. I warmly recommend giving it a go before trying anything more techie.