Knowing device type -- Retina/non-Retina

Question

Possible Duplicate:
Detect Retina Display

How can we know if a device has a retina display or not from objective C code?

Solution 1

if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]
    && [[UIScreen mainScreen] scale] >= 2.0) {
    // Retina
} else {
    // Not Retina
}

Solution 2

You can check the scale property on [UIScreen mainScreen] if it is 2.0 you are running on retina, if it is 1.0 you are not. You can also get the scale from the current CoreGraphics Context.

Comments

[Daniel T.]

Why would you need that?

[occulus]

What has the time zone got to do with Retina display?

[Stanislav Yaglo]

And the application will crash if the user runs it on iOS < 4

[Noah Witherspoon]

This is a terrible idea—it's not future-proof at all, and doesn't even account for the fourth-gen iPod touch, which also has a Retina display. The UIScreen class's scale property, as described in the other answers, is the correct way to do this.

[onnoweb]

Good point. I stand corrected.

[GorillaPatch]

Correct. This is why you want to check first if [[UIScreen mainScreen] respondsToSelector:@selector(scale)] is true. This is the general concept of how you would code to ensure backwards compatibility.

[shabbirv]

This should probably be >= 2.0 now (iPhone 6/6+)