RNDj is a simple tester for Android.
When run the first time, it will ask for you to open a .json file with the following structure:
{
"question 1" : "answer 1",
"question 2" : "answer 2",
"question 3" : "answer 3",
...
}When loaded, it will present you with 5 buttons: One at the top and four below.
The top button, containing a question, will reset the bottom counter when simpley clicked, or let you reselect a file when held.
The other buttons are possible solutions, with the correct one changing it's position in the grid from round to round.
This project was written in Android Studio. It is a side-project so I don't devote all that much time to it, as it is simple too.