5 Free Resources for iPhone App Development

-

[caption id="attachment_681" align="aligncenter" width="738" caption="Joe Hewitt's Three20 Project"]Joe Hewitt's Three20 Project[/caption]

With Apple's WWDC currently going on and the upcoming 3.0 iPhone OS getting closer to release, there are tons of new developers jumping onto the platform. Whether you're a new developer or have been developing for a while, here are some great free resources for designing and developing your iPhone Apps.

  1. Google Objective-C Data APIs

    Google generously provides a large set of their APIs in Objective-C for both Mac and iPhone development. These APIs include: Check out my previous post on How to add the Google APIs to your iPhone App project.

  2. Joe Hewitt's Three20 Project

    Joe Hewitt is the developer behind the popular Facebook iPhone App and the Mozilla Firefox plugin Firebug. He's created a new projected called Three20, which is a collection of iPhone UI classes, like a photo viewer, and general utilities, like an HTTP disk cache. The project and instructions on getting it into your iPhone App project are hosted up on GitHub.

  3. iPhone Photoshop PSDs

    It's always a good idea to start with a design before you start developing your iPhone App. It's also easier to show a potential client a PSD mock-up of the app before doing actual development even though Interface Builder makes it an easy process. Here are a few Photoshop PSDs to get you going. Note: If you are planning on using these for making an iPhone Apps website, make sure either you or your client has gone through Apple's Available on the iPhone App Store logo license program to avoid any legal issues. This can be found in your Apple Developer Connection Program Portal's Distribution -> App Store tab.

  4. OmniGraffle Stencil Kits

    If you're on a Mac and use Omni Group's OmniGraffle for wireframing or mindmapping web design, you can do the same with iPhone apps.Here are 3 iPhone Stencil sets for OmniGraffle. Also, Yahoo!'s set can be found on the Yahoo! Developer site with stencils for many other things and also in makes them available in Photoshop PSD format.

  5. Glyphish - iPhone Toolbar Icons

    The Glyphish designer has generously put out 80 free icons for use in your iPhone App's toolbar. These are all free and licensed under Creative Commons.

3 Bonus Resources

  1. Mercury Intermedia's iPhone UI Vector Elements for Adobe Illustrator.

    Working in Illustrator instead of Photoshop? These free vector elements great for designing.

  2. eddit's 120 iPhone Toolbar Icons

    While this one isn't free, it is a really good and worthwhile one. Eddie Wilson over at eddit has created 120 iPhone Toolbar Icons for sale at $69. If you want the vector format, it'll cost you a pretty $189 for the PSDs.

  3. Open Source iPhone Apps

Have I missed any others? Do you have any more free resources? Please feel free to share them in the comments!

Edit 6/23/09:

An additional Adobe Fireworks set of UI elements has been found thanks to Building43.

Fireworks toolkit for creating iPhone UI mockups by MetaSpark

Also check out Building43's video on designing iPhone Apps with Adobe Fireworks.