I just got my galaxy s5 today and the wifi keeps dropping connection. I honestly don't remember when it started happening because I was new to the phone and if anything was happening I did not realise it. I think it may have been due to an update the phone asked me to do. In better detail, i will be using my phone and randomly the wifi symbol at the top would disapear, and after a couple a seconds the little notification would come up at the bottom saying that I have been connected, realising something was wrong I waited for the symbol to disapear, and when it did I quickly went to the wifi settings and noticed that the router was not even on the list. Earlier today my mom said that she could connect but could not load anything on her note 3 and galaxy nexus. Because of this I am guessing it is and issue with the router. I have tried doing a simple 30 sec reset with no luck. I have also turned the phone on and off, but it still won't fix the problem. I am still investigating, I will test the other devices in the house and will also try other wifi networks. PLEASE if you have any idea how to fix this please share.