I have also been encountering this issue and opened the following question on SO which includes screenshots and version information: http://stackoverflow.com/questions/32878283/unable-to-profile-app-on-device-with-ios-9-0-1-using-xcode-7-7-0-1-or-7-1-beta
Since then, last Thursday I installed 9.0.2 when it was released and I was able to profile on the device that day.
Now today, opening up Xcode and Instruments, I am again no longer able to profile on that device and am receiving the "This device is not currently online." message.
I tried the recommendations in the Xcode 6.4 release notes as suggested by @mlchild however this did not generate any different results. The device is still disabled and the same message is displayed: "This device is not currently online." Yet the device is connected and I am able to run and debug on the device without any problems.
- What OSX build are you on? >> Version 10.10.5 (14F27)
- I see you're on iOS 13A344. >> Please see SO post - I tested with three different versions of Xcode (GMs and beta)
- Did you install Xcode 7.0 over a beta of 7.0, or was this a clean install? >> Xcode 7 was a fresh install; beta installed separately.
- Can you attach screenshots and file a radar at bugreport.apple.com so we can investigate? >> Please see SO post for screenshots; I will file a radar.
I'm not sure if this is related or not, but I also cannot delete installed apps from the Devices window:
- Window menu >> Devices
- Select iPhone device from left-hand side
- Select an installted app (any)
- Click the "-" button at the bottom of the "Installed Apps" section
- App disappears for a 1/2 second from the list, the screen refreshes and all apps are still listed including the one that was deleted.