What Do Arrows At Top Of Screen Mean Galaxy Ii Phone

What do icons mean at the top of the samsung galaxy s, Samsung galaxy phone icons chandelier. what are the different snapchat icons for iphone? for example i have red and white arrow and a blue and white arrow by another. What do the arrow pointing down on the top left hand, My samsung galaxy 4s has 2 arrows pointing down n the top left side of the screen what does this mean. what are the three grey arrows pointing downwards in the top.