I'm not an iOS or Mac developer but I do have one web project I was proud to work on in my last job:
VetSEA. Veteran Self-Employment Accelerator. I was on the three-man programming team that put this together though probably 75% of the code was written by my boss before I started. It's a pretty cool project that's geared towards helping veterans, especially those returning from service abroad, launch their own companies. Our contribution was the web platform which acts as a "hub" for vets, business coaches and mentors, investors, educational resources and so forth.