problem using tel: URL to initiate a call
<p>I'm trying to initiate a call from within an iPhone app.</p>

<p>This related code works and opens Safari as expected:</p>

<pre><code>[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"http://www.apple.com"]];
</code></pre>

<p>But, when I replace the http URL with a tel URL the resulting code does not invoke the phone app:</p>

<pre><code>[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"tel:3035551212"]];
</code></pre>

<p>No exceptions or alerts are generated (in the simulator or on a device).</p>

<p>Any idea what the problem might be with my invocation?</p>

<p>Thanks.</p>
