My iPhone charger won't charge my iPhone, but will charge other devices, why?

I've had my iPhone 4s for roughly 2 years now, no problems whatsoever. I've noticed, however, that over the past few months my charger usually takes a little wiggling to actually make my iPhone charge. It's gotten progressively worse, and tonight I found that I couldn't charge my iPhone with it at all!

It's charging via my Bose stereo right now. So I assumed it was simply my charger, and nothing to do with my iPhone. Just to be sure, I tried charging another device--my old iPod--with the same charger. It began charging the iPod, much to my surprise.

I'm so confused! Why is this happening? Is it my iPhone, or my charger? I'm at college and have no way of going to an Apple store.

It's the phone it most likely too lose inside I don't know how to fix that because mine broke because of that 2weeks ago

May be the problem is on the i pod, check your battery of i pod