When I first got my Motorola Droid, I downloaded a gazillion different applications, just because I could. The problem was, I could never use them all, and some would just take up so much space. Now, after smartening up, I have a core set of applications that I regularly use to manage my business and personal affairs. Note, these are in addition to the standard apps like Maps, Contacts, and Facebook.
In the order of most to least used, here they are:
K-9 Mail (free)
This is an email application that I believe is slightly more robust than the built-in GMail application. K-9 Mail allows extended signatures.
Handcent SMS (free)
Handcent allows you to customize/style your text messages with greater variety than the standard message application.
This application tracks your places and changes your ringer, notifications, and settings accordingly. You can use GPS, WiFi, and calendar to create various location settings.
This application extends the built-in calendar and incorporates more features, settings, and design styles to make it functional and appealing.
Google Voice (free)
It's made by Google. It's your telephone number. Need I say more?
Pandora Radio (free)
Your music comes alive with Pandora. Eliminate/minimize commercials, combine music genres, and create stations to suit your likes/interests.
TuneIn Radio (free)
Listen to radio stations all over the world.
PdaNet (free/paid available)
Use you Android device to tether with your laptop when there's no WiFi connection available. Free version doesn't permit HTTPS access. Sorry, no Facebook.
Ambling BookPlayer Pro ($8.99/free available)
This is a great audiobook player that recognizes and plays a variety of audiobook formats.
PocketCloud Pro RDP/VNC ($14.99/free available)
Use your Android device to connect to your RDP or VNC connection.
Angry Birds (free)
A game that you shoot a variety of birds at objects to solve puzzles.
Car Home (free)
Use your phone in the car.
Voice Recorder (free)
Use this recorder, then save and send the audio file to your email.
Use Evernote on your Android device. Cool.
Have you found an Android application you really love? Please let me know by posting a comment below.