I have been using this app since 2015 summer and I am the one who requested this product to be added to the list so that I can share my long experience and hope that the app developers listen to me. Although I am a civil engineer but this app is being used by every engineer aspiring to write the GATE exams. The app has been developed by the IIT for smooth conduction of online exams CBT and is used by every candidate to solve the numerical problems which are either of 1 mark or 2 marks with negative marking of 1/3 and 2/3 respectively, in which 2 marks carries the maximum weightage. So you can under that if you make a mistake you would lose high marks in an exam where even 1 mark matthers a lot ( believe me as I have experienced it first hand) .
Therefore if you do calculation mistake you would lose a good number of marks, hence fluency is a must in GATE and so fluency with this virtual calculator app is a must. But still there are problems which everyone of us aspirants face, those are:
1) programming error: while solving environmental engineering and maths questions I noticed that no matter what you do you will always get a few specific type of questions wrong. So beware.
2) slow: the app processes slowly hence we make mistake and loose time and marks.
3) incomplete: there are some calculations to which you won’t get the right answer in exponents.
4) hangs: sometime it can hang i.e. stop functioning do you have close it and do it all over again.
5) limit: there is always a limit to the input you can enter in a scientific calculator, but this app allows you to input much less than what other apps allow you input.
6) unreliable: since you can’t cross check any calculations you did instantaneously, it is very very very unreliable. I wonder why GATE organizers still use it.
7) No variables: there are no variable so you can’t make you solve complex problems easily.
8) No shift and No solve= : so it make solving matrices and equations tedious, lengthy and a waste of time.
9) no differentiations: solving differential equation impossible.
10) no integration: solving integral equations in impossible.
11) no replay : you can’t check your answer. to check your answer , you have to do it all over again.
12) different from usual scientific calculator: if you have a habbit of solving using a Casio fx-991MS kinds of scientific calculators then you have to break the habit. Because the method you use to input problems in Casio is much advanced, improved and user friendly, because GATE virtual calculator is primitive, under developed and full of bugs. You have to put each problem given inside a bracket one by once and note down the answer and repeat, similarly goes to numerator and denominator problems, where as in Casio you can’t put the whole problem at once and get the answer. If you use the Casio input method in GATE virtual calculator then you are bound to get the wrong answer no matter how careful you are.These are my genuine experience as I have using it for over 2 years now. In recent GATE exam it cost me a good numver of questions even though I practised heavily in this app for 7 months befor the exam. I request the developers to develop a new app which is much like Casio or improve this app to make it like Casio.