Battery tired iPhone 4S

If you take it to an Apple Store, they can run diagnostics to determine if it needs to be replaced. If it does, it is free of charge under warranty.

Thanks a lot ;-) do you know if it's possible to just walk in to the apple store, to have a dygnostic, or I'll have to make an appointment? Cheers :-)

You're welcome

You will probably want to make an appointment.

Thank you very much :-)