Yesterday’s iPhone SDK gave me one more reason to buy an iPhone when my current phone’s contract expires. I love discovering new software, and soon this rewarding experience will be part of the iPhone too. Developer reactions regarding the SDK are very positive overall, and it’s clear people are excited to begin working on the next cool iPhone app. Granted, many questions remain unanswered, but I don’t think that’s necessarily a bad thing. Between Apple’s Q&A and the Developer Connection, Apple has provided a solid starting point that appears reasonable for a majority of developers.

Most of the questions unanswered relate to licensing and distribution. Right now the programming process is much more important, giving developers time to experiment with the API instead of worrying about their distribution model. I’m sure some of these developers will share their idea of a perfect distribution model, and hopefully Apple will take some of these ideas into consideration. Instead of announcing a complete solution that might not work for everyone, Apple has laid out the basics to get people excited while keeping possibilities open for the numerous “what ifs” people are coming up with.

As far as technical “what ifs” go, some of the main ones are:

• Will software need to operate differently when running on EDGE versus Wifi?
• How in-depth will Apple review your software, and will Apple approve products competing with its services?
• Will 3rd party software have access to the iPhone UNIX subsystem?

There will certainly be software written that Apple won’t approve. We already know functions not included in the API, the file system out of the application’s scope, and the dock connector are out. But what’s to stop the developer from publishing this “forbidden” code? Users who wanted this same unapproved feature could download the source, compile, and install the software themselves. This has some obvious limitations:

• While the SDK is free, it costs $99 to test software on the iPhone (versus the iPhone simulator).
• Apple may require certificates even for apps in development, thus only allowing signed applications to be tested on the iPhone.
• Presumably, these Open Source projects are in some way using unsupported functionality, which could easily break in future iPhone updates.
• Users who don’t want to bother with compiling code will be disappointed.
• Would users be willing to pay for source code, or will developers be interested in releasing complex and unsupported functionality freely?

For the more ambitious user who has tinkered around with XCode, the ability to compile and install unsupported software for personal use is very appealing. While jail breaking violated terms of use, there doesn’t appear to be any legal problems in developing unsupported software. Apple won’t let you distribute the finished application to the masses, but it may be possible for other people to compile your source code on their iPhones. This is a good thing for both iPhone users and the Open Source community.

Subjects: Apple, iPhone, iPhone Development.