iOS 检测有没有安装其它应用 和ios9下要注意的地方

    UIApplication *app = [UIApplication sharedApplication];

    NSURL *url = [NSURL URLWithString:@"Trip://com.trip.tripmobile"];
    if ([app canOpenURL:url]) {

        NSLog(@"can  launch B app!");
        [app openURL:url];

    }else {

        NSLog(@"can not launch B app!");

    }

Trip: 为URL Schemes 

com.trip.tripmobile : 为Bundle identifier 

在项目中添加URL types

URL identifier 设为 com.trip.tripmobile

URL Schemes 设置为 Trip

iOS9 要设置白名单

<key>LSApplicationQueriesSchemes</key>

<array>

        <string>Trip8080</string>

</array>