iPhone SDK 2.2.1 based app should be launched on iPhone 3.0 OS device
<p>My app was built with SDK 2.2.1 version even before 3.0 beta appear.</p>

<p>User going to install my app to the last iPhone 3Gs with 3.0 FW version. Will my app behave differently with last iPhone?  Will items described <a href="http://developer.apple.com/iphone/library/releasenotes/General/RN-iPhoneSDK-3/index.html" rel="nofollow">here (3.0 OS Release Notes)</a> influence to my app which was build with 2.2.1 SDK?</p>

<p>For example Apple doc tell: <br>
<strong><em>FIXED: UINavigationController won't resize content view automatically if barStyle is changed to/from UIBarStyleBlackTranslucent.</em></strong></p>

<p><em>But my app use this style and I saw content view resize before with iPhone 2.2.1 OS...</em></p>

<p><br></p>

<p>What does it technically mean when I select 2.2.1 or 3.0 SDK as active in XCode for my project and build? Does SDK corresponded libraries linked statically?   </p>

<p>Thank you.</p>
