Short-range wire­less technology for computers, mobile phones etc — blotto hue (anag)

• It may be used with wireless devices
• Wireless networking protocol
• Technology standard named for a Danish king
• Wireless device technology
• Wireless linking protocol
• Communication system down? One's possibly used to the drill
• Gadgets communicate with it but old hotel gets confused

Wikipedia Word definitions in Wikipedia
Bluetooth is a wireless technology standard for exchanging data over short distances (using short-wavelength UHF radio waves in the ISM band from 2.4 to 2.485 GHz) from fixed and mobile devices, and building personal area networks (PANs). Invented by telecom ...