The following code snippet checks if SIM card is present or not as well if the device is capable of making the call such as non-sim ios devices
#import <CoreTelephony/CTTelephonyNetworkInfo.h>
#import <CoreTelephony/CTCarrier.h>
if ([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:@"tel://"]]) {
// Check if iOS Device supports phone calls
CTTelephonyNetworkInfo *netInfo = [[CTTelephonyNetworkInfo alloc] init];
CTCarrier *carrier = [netInfo subscriberCellularProvider];
NSString *mnc = [carrier mobileNetworkCode];
// User will get an alert error when they will try to make a phone call in airplane mode.
if (([mnc length] == 0)) {
// Device cannot place a call at this time. SIM might be removed.
} else {
// iOS Device is capable for making calls
}
} else {
// iOS Device is not capable for making calls
}
if ( ! [[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:@"sms:"]]) {
// iOS Device is not capable to send SMS messages.
}
Don't forget to add the CoreTelephony framework
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