跳转App设置页的方法

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];

说明：

UIKIT_EXTERN NSString *const UIApplicationOpenSettingsURLString API_AVAILABLE(ios(8.0));

官方注释
Used to create a URL that you can pass to the openURL: method. When you open the URL built from this string, the system launches the Settings app and displays the app’s custom settings, if it has any.

意思就是说可以用 UIApplicationOpenSettingsURLString 生成一个App设置页对应的url，使用openURL: 跳转到App设置页面，没有的话跳转手机设置页面。

下面是截图