可以從 UIDevice 的屬性 model 得到在現在執行的環境。例子如下：

NSString *modelname = [[UIDevice currentDevice]model];
if ([modelname isEqualToString:@"iPhone"]) {
  // iPhone
}
if ([modelname isEqualToString:@"IPod Touch"]) {
  // iPod touch
}
if ([modelname isEqualToString:@"iPhone Simulator"]) {
  // iPhone Simulator
}

 也可以通過宏定義區分 

#if TARGET_OS_IPHONE
    // iPhone Device

endif
if TARGET_IPHONE_SIMULATOR

// iPhone Simulator

endif
if !TARGET_IPHONE_SIMULATOR

// iPhone Device

endif</pre>


 ios設備版本的區分-iphone3gs,iphone4.... 

 ios提供了幾種c函數來獲得相應信息如下 

struct utsname u;
uname(&u); ///-----get device struct info
NSString *machine = [NSString stringWithCString:u.machine];

if ([machine isEqualToString:@"iPhone1,1"]) {
  // iPhone 1G
}
if ([machine isEqualToString:@"iPhone1,2"]) {
  // iPhone 3G
}
if ([machine isEqualToString:@"iPhone2,1"]) {
  // iPhone 3GS
}
if ([machine isEqualToString:@"iPod1,1"]) {
  // iPod touch 1G
}
if ([machine isEqualToString:@"iPod2,1"]) {
  // iPod touch 2G
}
if ([machine isEqualToString:@"iPod3,1"]) {
  // iPod touch Late2009
}
</pre> 


 或者

- (NSString ) platform
{
  size_t size;
  sysctlbyname("hw.machine", NULL, &size, NULL, 0);
  char machine = malloc(size);
  sysctlbyname("hw.machine", machine, &size, NULL, 0);///-----get device struct info

/
  Possible values:
  "iPhone1,1" = iPhone 1G
  "iPhone1,2" = iPhone 3G
  "iPhone2,1" = iPhone 3GS
  "iPod1,1"   = iPod touch 1G
  "iPod2,1"   = iPod touch 2G
  /
  NSString *platform = [NSString stringWithCString:machine];
free(machine);
  return platform;
}
</pre>