Let's see...here is what my phone (Motorola Atrix, from AT&T via Costco) has saved me...
-GAS BUDDY..I regularly save 10-20 cents a gallon on gas by searching. Today, for instance, I am driving a long distance. I will need to fill up, so I searched gas prices near home and near my destination. Home is 40 cents cheaper.
-Yard Sale Finder...so cool. It uses gps and listings from CL to point you to the nearest garage sales. I buy and resell a lot, so I then use my phone to pull up resale prices online to see if it is worth it to buy an item. I recently went to a sale that had a AeroGarden for $10. Almost passed it up, but checked and saw they were going for $50-60 in my area. chaaaa-ching.
-recipe apps...I use several, and it is soooo nice not to have to guess what is in something at the store.
-Cozi. best.app.ever. It is a family organizer. I have it on the phone and computer. I can add on shopping lists, to-do lists, appts and access them anywhere. My son had a therapist app, I was at work and forgot to tell DH. The app sent him a reminder, saving us a $50 cancellation fee.
That all being said, DH does NOT have one. He wanted one after using mine, but he has a prepaid cell that he rarely uses. We figured it out, and bought him an iPod Touch. That way he has his apps and games, but not a monthly fee.