The SDK is downloaded, I wrote my first iPhone app, but…
I can’t test it on the iPhone.
Unfortunately, in order to be an iPhone developer, you have to have a certificate that code-signs your software. In order to obtain this certificate, it is necessary to enroll in the iPhone Developer Program, which costs anywhere from $99 to $299. At this point, that isn’t worth it for me.
Conclusion: iPhone development to be continued at a later time.