iOS 查看手机的各种属性

UIScreen *mainScreen = [UIScreenmainScreen];

    // 需要注意 coordinateSpace 属性 iOS 8 以上才支持

NSLog(@"Screen bounds: %@, Screen resolution: %@, scale: %f, nativeScale: %f",

          NSStringFromCGRect(mainScreen.bounds), mainScreen.coordinateSpace, mainScreen.scale, mainScreen.nativeScale);

输出的结果：

Screen bounds: {{0, 0}, {414, 736}}, Screen resolution: <UIScreen: 0x7f9193403810; bounds = {{0, 0}, {414, 736}}; mode = <UIScreenMode: 0x7f9193403680; size = 1242.000000 x 2208.000000>>, scale: 3.000000, nativeScale: 3.000000