Why do our jeans pants have a small pocket just above the front right pocket?

Though I use jeans pants very often, I get this doubt rarely when:

• In train, while sleep in upper birth, I shift coins from back pocket to this; to avoid fall on passengers in lower birth.
• To keep 5 rupees coin Saturday early morning, which serve ticket cost to my village; rather struggling for change as it's very first stop in that route.
• sometimes to pen-drive so that I may copy some nice movies when visit friends; but never missed to check tiny pocket before dropping it to wash.

I pen down how it got useful to me. But sometimes it's not easy to take stuff out of it without making the scene awkward.

Why this colaveri-de...Was it something useful that was added or it is just a fashion thing?

One fine day remembered when surffing on net, figured out the actual reason behind & that was...

Back in the 1800s, cowboys used to wear their watches on chains and kept them avoid getting broken. Levis introduced this covering mainly cowboys and it continued then on...
http://www.levisguide.com/watchpocket/watchpocket.html

way back Gandhi ji used it without pant, forget pockets LoL:)

You may see people find it useful in their own ways like coins, keys, small ipod, lipstick/lip balm, tissue pocket & wand holder(Harry Potter fans)etc. already said just individual own ways.