How to make a call programmatically in iOS

Objective C

NSString *phNo = @"999991";
NSURL *phoneUrl = [NSURL URLWithString:[NSString  stringWithFormat:@"telprompt://%@",phNo]];
    
if ([[UIApplication sharedApplication] canOpenURL:phoneUrl]) {
  [[UIApplication sharedApplication] openURL:phoneUrl];
}
else{
  // Show alert Call facility is not available in this Device!!
}

Swift 3.0

 /// Telephone call by number
    func telephoneCall(number: String) {

        let trimmed = number.replacingOccurrences(of: " ", with: "")

        let phoneURL: URL = URL(string: "telprompt://\(trimmed)")! // Removed white space

        if UIApplication.shared.canOpenURL(phoneURL) {
            if #available(iOS 10.0, *) {
                UIApplication.shared.open(phoneURL, options: [:], completionHandler: nil)
            } else {
                UIApplication.shared.openURL(phoneURL)
            }
        } else {
           // Call facility is not available on your device
        }
    }

– How to make an iOS App
ktrkathir