Answer:
What kind of dog keeps the best time?
I belong to you but others use me more often than you do. What am I?
I'm a precious stone in a pack of cards. What am I?
So simple, that I can only point. Yet I guide men all over the world.
If you drop me, I'm sure to crack. Give me a smile and I'll always smile back. What am I?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.