App Review: USPS Mobile
Website: https://www.usps.com/mobile/info.htm
Works with: iPhone, Android, Blackberry
Free. It has the ability to scan and track packages. The app also gives information on zips, blue box locations and even allows you to put your mail on hold.
Tested on: iPhone (running 6.1.3)
What I like about it: I can look-up zip codes, track packages, and find drop boxes while on the road (with their various pickup times).
Gotcha’s: There doesn’t seem to be a way to easily order stamps?
I use USPS Mobile for: convenience, I don’t like the USPS.com website all that much