XCode 7

I'm able to use it, except I can't get the simulator to work.

I have this problem also, with the error:

DTAssetProviderService could not start DTXConnection with Simulator 'iPhone 6s'. Check the system log for errors.

Investigating the system log, I have these xcode-relevant messages:

Jun 14 11:16:42 OAKM00536250A Xcode[2663]: +[DTServiceHubClient localConnectionWithAuthorization:returningServerPid:]: failed to establish connection with DTServiceHub service '/Applications/Xcode.app/Contents/SharedFrameworks/DVTInstrumentsFoundation.framework/Resources/DTServiceHub'
Jun 14 11:16:42 OAKM00536250A Xcode[2663]: Xcode[2663]: [error] 'mach_msg_send' failed: (ipc/send) invalid destination port (268435459)
Jun 14 11:16:44 --- last message repeated 1 time ---
Jun 14 11:16:44 OAKM00536250A com.apple.xpc.launchd[1] (com.apple.imfoundation.IMRemoteURLConnectionAgent): Unknown key for integer: _DirtyJetsamMemoryLimit

Jun 14 11:17:04 OAKM00536250A Xcode[2663]: CompanionProxy: _SocketReadCallback:128 (0x0x7000047d4000): Failed to receive response from AMDevice 0x7fce2dddf7c0 {UDID = aac0ab6603e5d648dbfdd1ddd929795cae7d4983, device ID = 5, FullServiceName = d0:25:98:5a:28:dc@fe80::d225:98ff:fe5a:28dc._apple-mobdev2._tcp.local.}: 0xe8000084
Jun 14 11:17:04 OAKM00536250A Xcode[2663]: CompanionProxy: _SocketReadCallback:206 (0x0x7000047d4000): Stopped listening for paired devices from AMDevice 0x7fce2dddf7c0 {UDID = aac0ab6603e5d648dbfdd1ddd929795cae7d4983, device ID = 5, FullServiceName = d0:25:98:5a:28:dc@fe80::d225:98ff:fe5a:28dc._apple-mobdev2._tcp.local.}: 0xe8000084

>does anyone happens to know if XCode 7 runs on macOS 10.12 alongside with XCode 8 Beta?

From the Xcode 8 Release Notes:

I get the same error as well.

The app actually still builds and you can run it manually from the device but isn't connected to Xcode which is the big problem.