My iPhone 6+ has shown little to no drain while connected to my 42mm SS Apple Watch. I mentioned this before, but while golfing for two plus hours, the iPhone 6+ was in my golf bag pocket and charged to 100%. I had the Apple Watch running the Workout Other the whole time and even responded to several texts using siri or canned responses and had maybe 30 notifications. I checked the time several times as well. At the end of the round, my iPhone 6+ was either at 100% or 99% and never lower and I do this every week. I was not running any other applications that could have drawn down the battery, but I was doing plenty and it had basically no impact on the iPhone 6+ and I am running the latest version of O/S.