I have Samsung galaxy S3 At&t. I'm running android version 4.1.2. My issue is I have no wifi signal where other phone and other GS3 and my Samsung table does. I have done a restore on my phone thinking that it might have been something running in my background. That worked for about 2 weeks then I started to have the same problem again. I cant figure out what is wrong with it. I have to be right next to my router for my wifi to work and have any kind of speed. It will stay connected threw out my house, but it just wont refresh my facebook or anything that uses the internet. I really need help.