Browse Photos in Android's Default Directory?

Does anybody have an example or method to browse photos in Android's photo locations? I'm using Standard rather than Developer version.

I had this working photo browser in my app (albeit it only returned their file names in a list), until I changed my phone and then noticed that my app no longer works on the new phone, which stores images on an SD card rather than internal storage. I guess what I need is either a way to allow the user to specify the photo/image storage directory, or a command that will return the directory that the OS is using. Anybody successfully done this yet?