App store upload and setting deployment target in iphone

i have built my app using xcode 4, & its workin开发者_如何学Cg fine on ios 3.1.3 device if i set my deployment target to 3.1.3 , it is working fine ios 4 and if i set the deployment target to 4 ,my doubt is while uploading to app store what deployment target should i set?????

thanks in advance

The answer is YES and NO.

YES: Because it will run on iOS 3.1.3 for the APIs and methods supported till 3.1.3

NO: Because it will not support the APIs introduced in iOS versions > 3.1.3

Example: If you integrate SMS functionality as it was introduced in iOS 4.0