Think submarines are fun? Wait until you try this app! This game is an addictive and fun harbor simulation game that you will not want to put down! Submarine Rules and Regulations: 1. NO COLLISIONS! submarines cannot 'bump' into each other. Keep your distance, accidents can happen even without a bump! watch out! Sometimes you can be lucky that they don't collide since they are not in the same profundity. Beware! don't play with your luck!2.There are 3/4 colored ports (red, blue and yellow), you need to park boats according to their color. 3. If you try to park a sub in the wrong deck/port you will crash!How to play? Just drag the sub to the proper entrance.