这个代码怎么样，如果新版本发布，你将标识与最后知道的设备

- (NSString *)getModel {
    size_t size;
    sysctlbyname("hw.machine", NULL, &size, NULL, 0);
    char *model = malloc(size);
    sysctlbyname("hw.machine", model, &size, NULL, 0);
    NSString *sDeviceModel = [NSString stringWithCString:model encoding:NSUTF8StringEncoding];
    free(model);                              
    if ([sDeviceModel isEqual:@"i386"])      return @"Simulator";  //iPhone Simulator
    if ([sDeviceModel isEqual:@"iPhone1,1"]) return @"iPhone1G";   //iPhone 1G
    if ([sDeviceModel isEqual:@"iPhone1,2"]) return @"iPhone3G";   //iPhone 3G
    if ([sDeviceModel isEqual:@"iPhone2,1"]) return @"iPhone3GS";  //iPhone 3GS
    if ([sDeviceModel isEqual:@"iPhone3,1"]) return @"iPhone3GS";  //iPhone 4 - AT&T
    if ([sDeviceModel isEqual:@"iPhone3,2"]) return @"iPhone3GS";  //iPhone 4 - Other carrier
    if ([sDeviceModel isEqual:@"iPhone3,3"]) return @"iPhone4";    //iPhone 4 - Other carrier
    if ([sDeviceModel isEqual:@"iPhone4,1"]) return @"iPhone4S";   //iPhone 4S
    if ([sDeviceModel isEqual:@"iPod1,1"])   return @"iPod1stGen"; //iPod Touch 1G
    if ([sDeviceModel isEqual:@"iPod2,1"])   return @"iPod2ndGen"; //iPod Touch 2G
    if ([sDeviceModel isEqual:@"iPod3,1"])   return @"iPod3rdGen"; //iPod Touch 3G
    if ([sDeviceModel isEqual:@"iPod4,1"])   return @"iPod4thGen"; //iPod Touch 4G
    if ([sDeviceModel isEqual:@"iPad1,1"])   return @"iPadWiFi";   //iPad Wifi
    if ([sDeviceModel isEqual:@"iPad1,2"])   return @"iPad3G";     //iPad 3G
    if ([sDeviceModel isEqual:@"iPad2,1"])   return @"iPad2";      //iPad 2 (WiFi)
    if ([sDeviceModel isEqual:@"iPad2,2"])   return @"iPad2";      //iPad 2 (GSM)
    if ([sDeviceModel isEqual:@"iPad2,3"])   return @"iPad2";      //iPad 2 (CDMA)

    NSString *aux = [[sDeviceModel componentsSeparatedByString:@","] objectAtIndex:0];

//If a newer version exist
    if ([aux rangeOfString:@"iPhone"].location!=NSNotFound) {
        int version = [[aux stringByReplacingOccurrencesOfString:@"iPhone" withString:@""] intValue];
        if (version == 3) return @"iPhone4"
        if (version >= 4) return @"iPhone4s";

    }
    if ([aux rangeOfString:@"iPod"].location!=NSNotFound) {
        int version = [[aux stringByReplacingOccurrencesOfString:@"iPod" withString:@""] intValue];
        if (version >=4) return @"iPod4thGen";
    }
    if ([aux rangeOfString:@"iPad"].location!=NSNotFound) {
        int version = [[aux stringByReplacingOccurrencesOfString:@"iPad" withString:@""] intValue];
        if (version ==1) return @"iPad3G";
        if (version >=2) return @"iPad2";
    }
    //If none was found, send the original string
    return sDeviceModel;
}

- (BOOL)deviceiPhoneOriPod
  {
    NSString *deviceType = [UIDevice currentDevice].model;
    if([deviceType rangeOfString:@"iPhone"].location!=NSNotFound)
      return YES;
    else
      return NO;
  }

if([UIDevice currentDevice].userInterfaceIdiom==UIUserInterfaceIdiomPad) {
    //Device is ipad 
}else{
    //Device is iphone
}

你可以在GitHub上查看GBDeviceInfo，也可以通过CocoaPods获得。它提供了简单的API来检测各种属性，支持所有最新的设备:

设备的家庭

[GBDeviceInfo deviceDetails]。family == GBDeviceFamilyiPhone;

设备模型

[GBDeviceInfo deviceDetails]。model == GBDeviceModeliPhone6。

欲了解更多，请参阅Readme。

你可以像这样使用UIDevice类:

NSString *deviceType = [UIDevice currentDevice].model;

if([deviceType isEqualToString:@"iPhone"])
    // it's an iPhone

下面提到的代码片段应该有帮助:

 if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
   // iPhone device
 }
 else if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {
   // iPad device
 }
 else {
  // Other device i.e. iPod
 }