HI Jane
Here are a few for the iPhone I can recommend and use.
LunaSolCal
Hyperfocal .... has a person using a tripod silhouetted
MyRadar Good to see what is going on weather wise.
Flashlight
Compas
Navigon This a little more expensive but has all the maps and gets you there.
Also great for making special places.
Do search for others, they are sort of addictive :)
al