For my next iphone application, I intend to use some open source library.
The big question is : How to get them work for iPhone ???

First of all, I installed 'darwinport' to get some usefull command line tool (wget for instance)

I choose to have all my open-source library in the same folder
/Users/olivier/Documents/IphoneDevProjects/3rdParty
with the following subfolder :

• build-os : inflatted packages to build libraries running on the device
  
• build-sim: inflatted packages to build simulator libraries
  
• iphone-os : preffix where libraries, headers, ... are installed by 'make install' for the device
  
• iphone-sim : preffix where libraries, headers, .. are installed by 'make install' for the simulator
  
• iphone : repository for library created by 'lipo' command (to use in XCode)
  
• pkg : where I stored all the packages
  
• script : usefull script
  

Here is how I get them to compile :

• ZBar bar code reader (sourceforge)
  
• need ImageMagick
• need jpeg library
• libssh2 (sourceforge)
• need libgpg-error
  
• need libgcrypt
  
• need gnupgp
• tesseract
• need libtiff
• need jpeg library
• libcurl
• need gnutls
• libgcrypt
• gnupgp
• libtasn1
• need libssh2
• ODE (http://www.ode.org/)
  

For theses library to work on the simulator, check this page :  compile library for iphone simulator.

When I tried to cross-compile those lib on my own, I search on the web to get some help.
Here are the following site which help me founding my way :
http://latenitesoft.blogspot.com/2008/10/iphone-programming-tips-building-unix.html