I have the field test mode DBM reading for cell service enabled most all of the time, and usually I get about -100 to -116 in my house (I surprisingly still get 10mbps down with LTE and no dropped calls). The service is obviously pretty bad, so I typically turn cellular data off and turn wifi on. This allows calls and SMS while iMessage and everything else is fine on WiFi. Battery is greatly helped out by doing this. Anyway, since iOS 9, the reading at the top often drops to -120, sometimes lower, which is where things tend to get really bad. Haven't exactly tested to see if actual usage has deteriorated, but "No Cell Coverage" is now showing in the battery usage list. It was up to 10% of my battery usage earlier!! Anyone else noticing anything similar? I really really wish I could use T-Mobile so I could turn on Airplane Mode and turn on wifi and still get all my calls/texts, but no... They only have 2G, "Partner", and shaky LTE in my area. Not an option.