A steep price for a calculator ...

But it is worth it. I am one of the people who today their TI-85 rumschleppen with it. Already alone because then no colleagues want to borrow your calculator. The app can not replace him, but that would be asking too much. Finally my TI-85 at that time cost 100 marks and the app costs less than a tenth of that. But the range of functions can already be seen. Quick time plotting a function - no problem. Multiply matrices? Logically. Complex numbers anyway. And statistical calculations are also possible. It's fun to try everything.
With the operation I found myself immediately familiar.
For people who enjoy mathematics have definitely recommended. From me there's 5 star.