Debug IPhone App on 3.1.2 Phone

I recently finished my first IPhone app and want to test it on my device now. I registered (and paid) for an Developer Account and mana开发者_开发技巧ged to install the required certificates.

Unfortunately my device is on firmware 3.1.2 (which I don't want to upgrade). My SDK only shows 3.1.3 as possible Target. As a result it can't be installed on my 3.1.2 device.

Where can I set/change to target platform ? Otherwise my App would only run on the newest firmwares, right ?

Instead I want to provide it to every User with OS > 3.0

I think you should change the "Base SDK" in the settings of your project. Usually this will be the lowest version you will see in the Targets list.

See apple documentation here

You can set the deployment target in your Target Settings for your app. Set it to the lowest version of the iPhone OS you wish to support.

By doing this, you need to be careful which features you use in your app, and check for their availability at runtime before using them. If you use features that are available in 3.1 but not 3.0 for instance (such as the camera overlay API), then you should check for the existence of these APIs before calling them to prevent crashes on devices that are running 3.0.

You also need to weak link against frameworks that are only available in later versions than the one set in your deployment target setting.

Check out the SDK Compatibility Guide