I recently did some fishing in the Golden Trout Wilderness and wanted to pass along an endorsement for a smartphone app I bought that was very helpful. I found it on california-flyfishing.com

It's Stream Map USA and I bought the iPhone version. It helped me find all the tiny tributary streams on the South Fork of the Kern and tracked me with GPS on its maps while I hiked. I was able to store waypoints as I traveled and the maps worked even when I didn't have phone service which was most of the time.

I was skeptical when I bought it for $8.99 but have to say, it's worth it!