I have had many iphones in the past and always jailbroke them. One of the tweaks I installed let you switch between the db meter and bars if you tapped the wifi bars. I got a new job and a totally new iphone 6+ which I restored from an icloud backup. The 6+ was never jailbroken yet I still have the wifi db meter tweak somehow. My coworkers would like to have it too, yet I can't find a way to do it. All the guides I can find will show how to do it for cellular, but not wifi.