Using URL scheme to open Settings.app

gistfile1.m

// Turn on Location Services?
[NSURL URLWithString:@"prefs:root=LOCATION_SERVICES"]];

// Set up Twitter?
[NSURL URLWithString:@"prefs:root=TWITTER"]];

// Hook up a Bluetooth device?
[NSURL URLWithString:@"prefs:root=General&path=Bluetooth"]];

// Change app settings
[NSURL URLWithString:@"prefs:root=Apps&path=<#Your App Display Name#>"];