I am new in PHP with at most 1 month exp. And I am writing a PHP SDK for a cloud storage service and I am hoping not make any big mistakes so that most my target users (PHP developers) can use this SDK without trouble-shooting.
Now I am worrying about which version the SDK should be based on. PHP 5.3 is good with Namespace feature, and I can see AWS PHP SDK (http://aws.amazon.com/sdkforphp) is based on PHP 5.5. But I think the newer my SDK PHP version is, the less user will be able to use it because of backward compatibility.
So please tell me what is the convension in PHP version supporting? Or a more closed question: Is it a bad idea for my SDK to be based on PHP 5.3?
Thanks to @JohnConde and now I realized the real question should be which is the most used PHP version and it's already answered Which PHP 5 Version is most commonly used?.