NSMutableString * str=[[NSMutableString alloc] initWithFormat:@"tel:%@",@"186xxxxxxxx"];
// NSLog(@"str======%@",str);
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:str]];

NSMutableString * str=[[NSMutableString alloc] initWithFormat:@"tel:%@",@"186xxxxxxxx"];
UIWebView * callWebview = [[UIWebView alloc] init];
[callWebview loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:str]]];
[self.view addSubview:callWebview];

NSMutableString * str=[[NSMutableString alloc] initWithFormat:@"telprompt://%@",@"186xxxxxxxx"];
// NSLog(@"str======%@",str);
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:str]]