 <p>This works on ios 8 - just add seconds since 00:00 1 Jan 2001, so to open cal on 2 Jan 2001</p> <pre><code>NSString* launchUrl = @"calshow:86400"; [[UIApplication sharedApplication] openURL:[NSURL URLWithString: launchUrl]]; </code></pre> <p>I'm using RubyMotion, so my code looks something like this:</p> <pre><code>url = NSURL.URLWithString("calshow:#{my_date - Time.new(2001,1,1)}") UIApplication.sharedApplication.openURL(url) </code></pre>