going thru junctions app for Android mobile phone

There are 50 situations with junctions on paper; in every situation (which are 2D) takes part 2 up to 4 cars. User chooses, then he will pass the junction - first one, second or so on. If he is right - the cars are mooving and passes junction, if he is wrong - there is an accident and user will see some explanations (text). After that he sees the situation again, and then he answers correct, gets another situation.