After reading several posts on this matter, I thought I was all clear about my options, until I actually submitted the update to Apple... 

To my understanding, there are two main approaches for developing for both iPad and iPhone:

1. Create two targets within the same project, one for iPad and iPhone each. Then push both of them to App Store updates, and App Store would check the Base SDK, Deployment Target, and Targeted Device Family to distribute the appropriate app to each OS/device.
2. Have one target, but two sets of views (i.e. xib files), for iPad and iPhone each. Using conditional statements to detect the device type and load the appropriate views. Then iPad and iPhone will download the same target.

I took the first approach, but I am having trouble uploading the iPad target. I kept getting the error that the uploaded app should support the OS supported by the previous version. What should I do? Should I just make the Base SDK to the latest version and Deployment Target to the oldest version I want/need to support?