Hi my name is Sandie and I am only a newbie both to this forum and to the I Phone 4s. I have heard via friends how very helpful you all can be so here goes with my question. I have only had my I Phone 4s for 3 days so am still finding my way around it. When my phone is turned on but not in use the screen stays on resulting in using the battery un-necessarily. Can someone please tell me where I have to go to alter this so that the screen goes into "sleep mode"?????? Many thanks in advance.