Accessory maker Kensington unveils a new line of security devices for iOS and Mac users. The SecureBack line includes the $90 SecureBack Protective Folio Case & Lock for iPad and $80 PowerGuard for iPhone 4 and 4S. Kensington also announced a pair of iMac security devices, the $100 SafeStand for 27-inch iMacs and the $80 SafeDome for Macs. The company also unveiled a $45 ClickSafe laptop keyed lock for the MacBook Air line and $50 SecureBack Security Case for New iPad.”]