iPhone 4S Won't Charge After iOS7 Update

After installing ios7 update my phone fails to charge properly.

When on: plug in charger : 'this device may not be supported' --- my option? 'dismiss'
on every plug in this message appears.

When off: battery icon appears when charger is plugged in, after 3 seconds fades to black, on pressing home button it shows battery icon again.

I've tried all solutions provided to me by phone technical support, no help.

My phone currently charges to 3-5% when left off, comes back to life when turned on, but doesn't hold charge for more than 5 min and dies.

When plugged into mac/itunes everything works exept charging.

I've tried other cables/chargers, nothing

Also no longer supports my fm car transmiter that I purchased 'this device may not be supported' --- my option? 'dismiss'

The reason for buing an iphone was to have my music on the go and be able to play it/record my creative ideas: now it has become a paper weight and source of frustration.

I will be taking it in to an apple dealer today to check if its a hardware issue, but there have been no hardware problems or any damage before or after ios7 instal.

Questions:

how do i get it to charge? how do i get it to support my purchased iphone accesories?