[[UIApplication sharedApplication] openURL:url];

通过给url不同的值，可以实现调用系统自带 电话／短信／邮箱／浏览器／...

1、调用 电话phone

[[UIApplication sharedApplication]  openURL:[NSURLURLWithString:@"tel://800888"]];

拨打电话之后不跳转回app

[[UIApplication sharedApplication]  openURL:[NSURLURLWithString:@"telprompt://800888"]];

拨打电话之后跳转回app

2、调用自带 浏览器safari

[[UIApplication sharedApplication] openURL:[NSURLURLWithString:@"http://www.abt.com"]];

3、调用 自带Mail

[[UIApplication sharedApplication] openURL:[NSURLURLWithString:@"mailto://admin@abt.com"]];

4、调用 SMS

[[UIApplication sharedApplication] openURL:[NSURLURLWithString:@"sms://800888"]];

5、调用 app Store

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"itms-apps://"]];

6、调用 iBook

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"itms-books://"]];

7、调用 Map

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"maps://"]];

8、调用Facetime

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"facetime://"]];

9、调用Music

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"music://"]];

10、跳转到系统设置相关界面

[[UIApplication sharedApplication] openURL:[NSURL

URLWithString:@"prefs:root=WIFI"]];

以下为设置的跳转关键字

About —prefs:root=General&path=About

Accessibility —prefs:root=General&path=ACCESSIBILITY

Airplane Mode On —prefs:root=AIRPLANE_MODE

Auto-Lock —prefs:root=General&path=AUTOLOCK

Brightness — prefs:root=Brightness

Bluetooth —prefs:root=General&path=Bluetooth

Date & Time —prefs:root=General&path=DATE_AND_TIME

FaceTime — prefs:root=FACETIME

General — prefs:root=General

Keyboard —prefs:root=General&path=Keyboard

iCloud — prefs:root=CASTLE

iCloud Storage & Backup —prefs:root=CASTLE&path=STORAGE_AND_BACKUP

International —prefs:root=General&path=INTERNATIONAL

Location Services —prefs:root=LOCATION_SERVICES

Music — prefs:root=MUSIC

Music Equalizer —prefs:root=MUSIC&path=EQ

Music Volume Limit —prefs:root=MUSIC&path=VolumeLimit

Network —prefs:root=General&path=Network

Nike + iPod —prefs:root=NIKE_PLUS_IPOD

Notes — prefs:root=NOTES

Notification —prefs:root=NOTIFICATIONS_ID

Phone — prefs:root=Phone

Photos — prefs:root=Photos

Profile —prefs:root=General&path=ManagedConfigurationList

Reset —prefs:root=General&path=Reset

Safari — prefs:root=Safari

Siri —prefs:root=General&path=Assistant

Sounds — prefs:root=Sounds