My Must Haves:
Wifi Analyzer - gives you a graph displaying the strength and channel of all wifi signals in the area - great for picking a clear channel in a busy area and an appropriate signal strength. (90% of people leave their router at the default channel, leaving 1 and 11 wide open ).
Weatherbug - small desktop widget, includes radar maps in the app, and seems to be lighter than the WeatherChannel app.
Scoreboard - the google sports app, seems better organized and lighter than Sportstap (and includes tons of soccer for those of you who weren't born in the us), but doesn't have as many links to team info/news as Sportstap.
DockRunner - gives you the alarm clock view without having to buy the $30 stand.
Google Sky - turn it on and point it at that constellation you're looking at. It will tell you what major constellations, planets and galaxies are in that direction.
Any Cut - allows you to create desktop shortcuts to more than just apps. For example, I have shortcuts to the fantastic "Battery Usage" and "Running Services" pages that are buried deep in the settings menu. The one tells you how much each feature of the phone is killing your battery, the other tells you what services are running, with how much memory, and lets you kill the ones you don't want. I like the built in task manager better than the 3rd party apps like Taskiller.
Astro - file manager, which isn't built in to the phone apparently.
Backgrounds - easily find and change backgrounds.
Honorable Mentions
Shapewriter - lets you type on the screen by dragging through all the letters instead of pecking, lets me type one-handed much faster. The autocorrect feature works well in that it usually shows the word you were too ham handed to type (draw?) correctly, but it sometimes has problems pasting that into the field (i.e. it stays stuck with it's first choice).
Speedtest - lets you objectively determine how fast your connection is (and shame all your iPhone wielding friends and their AT&T network).
Listen - google app for downloading podcasts. (This is actually really frustrating and limited, but it's the best I've been able to find so far for podcasts).
Mystique - kind of cool 3D adventure type game (by kind of I mean barely).
Open Home - more customizable home screen, I haven't played around with this a lot but it has potential.
Picsay - touch up (or radically alter) those 5mp pictures. Plus, you can prove to the doubters that yes, Droid can do pinch zoom, it's just some stupid legal issue.
Want to haves:
Podcasting App - can
Copy and Paste App - right now you need keyboard shortcuts or 2nd level menus to copy text.
Pich Zoom browsers/full OS workarounds - double tap works for text columns, but face it, the iPhone pinch-zoom is awesome.
Google Docs App - this has to be coming sometime soon, right?
Games - this is one of the few areas (besids cut & paste and pinchzoom) where the Droid gets trounced by the iPhone.
Widgets - the weather, calendar, wifi, sports, etc. widgets are great, but there's a ton more potential here.
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