We might as well start to compile a list of apps that work well with 2.1 and N1, and what don't. A list of recommended apps might be good too--especially those that work well to enhance the N1 (like a flashlight app that turns on the LED). If folks contribute, I will update the first posts so visitors can get a quick glance...
Updated on 7-Jan-2010 at 7:50 PST
[Free] Handcent SMS works, great SMS application
[Free] Handcent Keyboard works, a good T9 IME for quick texting (still maintains voice input)
[Free] Battery Indicator works, a light weight task-bar icon that gives you battery %
[Pay ($0.99)] Advanced Task Manager: Works - Lets you manage active tasks and shut down all active tasks to help clear up memory/speed up the phone.
[Free] AK Notepad: Works - Very nice notepad application.
[Free] Amazon: Works - Gives full access and navigation to the store, wishlists, barcode scanning, and picture searches for items off of Amazon.
[Free] Astrid: Works - To-do list with flags to get things done, scheduling of to-do items, etc.
[Free] ASTRO: Works - File manager for the phone (one of my must-have apps)
[Free] Backgrounds: Works - Huge catalog of (non-live) backgrounds for the phone. Backgrounds look fine on the display.
[Free] Bump: Works - Contact information and file sharing application (cross-platform, files can be transfered to the iPhone).
[Free] Cestos: Works - Multi-player game much like marbles.
[Free] chompSMS: Works - Alternative to built-in SMS messenger. Does a better job with organizing the conversation visually.
[Free] Dial Zero: Works - Application to automatically make your way through phone trees to get to where you need to go (list is user-updated, so it's good, but not complete).
[Free] Documents to Go: Works - Read PDF, Word, etc. documents (pay version allows editing and Excel access).
[Free] Dolphin Browser: Works - Alternative brower that supports multi-touch pinch zooming and tabbed browsing.
[Pay ($0.99)] Doodledroid: Works - Android drawing application. Good to give kids to pass the time, or to pass notes when you want to draw out something.
[Free] Draw!: Works - Not as full-featured as Doodledroid; basic drawing application.
[Free] DroidDice: Works - Dice roller (d4-d100).
[Free] Google Sky Map: Works - Google's viewer that allows you to find constellations based on your current location.
[Free] Google Translate: Works - Basic Google translation service (many languages supported), also supports audio translation.
[Free] GPS Status: Works - Visual display of current access to GPS satellite to determine signal strength.
[Free] i Music: Works - Online music library download application.
[Pay? (I don't remember)] Keeper: Works - Secure password vault for the phone. Supports significant encryption and self-destructs after a number of failed login attempts.
[Free] Layar: Works - Use the camera + lists to find items using the camera as a visual interface.
[Free] Magic 8 Ball: Works - Really, it's just a magic 8 ball.
[Free] Metal Detector: Works (and wow it's more sensitive than my G1 ever was) - Detects metals using the built in magnetometer.
[Free] Mobile Banking: Works - Online banking application used by many banks to access account information.
[Free] Mobile Defense: Works - Application allows for tracking of your phone remotely from a website and the ability to permanently shut down the phone (not the SIM card) remotely.
[Free] Movies: Works - Flixter Movies lets you find theater show times, reviews, etc.
[Free] Open Table: Works - Restaurant reservation application.
[Free] Pandora: Works - Web based streaming music service.
[Pay ($0.99)] Power Manager: Works - Set up automatic features that turn on/off features and screen brightness based on current battery levels.
[Free] Ringdroid: Works - Create ringtones from MP3 files.
[Free] Sherpa: Works - Basic yellow pages application built into a map interface.
[Free] Shop Savvy: Works - Barcode/product search tool for finding prices of items on the web.
[Free] Solitaire: Works - Multiple solitaire games.
[Free] The Weather Channel: Works - Temperature, forecasts and radar images. (Yes I know it's built in, but sometimes I want radar)
[Free] Tiny Comics: Works - Database of current and upcoming comic releases searchable by publisher.
[Pay ($19.99)] Touchdown (Used 2.0 Build): Works - Full-featured MS Exchange syncing application. Syncs contacts, e-mail, calender, and to-do list. A must-have application if you use Exchange.
[Free] Trap!: Works - Simple game.
[Free] Word Up! (Free Version): Works - Word search game.
[Free] My Account: Works (Sort of, but yes it works). The application doesn't recognize the phone and provides an error message, but once you pass that message it works just fine giving information about minutes used, messages left, billing, etc.
[Free] Contact Owner: Works (Sort of) - Display selectable contact information on the lock screen in case the phone is lost (I put in my work address and phone number). This application works, but it kind of screws up your pattern login page. You have to fail the login once in order for it to scale back to full screen size. Workable, but a bit of a pain. An absolute must-have app.
[Free] Android Manager Free, Works, A task manager, application manager, and file manager
[Free] Barcode Scanner, Works, Scans QR and other codes and shopping services
[Free] City Caller ID, Works, Adds city and state of the incoming call
[Free] Goggles, Works, Take a picture, search based on the picture
[Free] Key Ring, Works, Keeps a copy of all your store discount cards/club (barcodes) so you won't have to carry them
[Free] T-Mobile Visual Voicemail, Works, the same as VVM from other devices
[Free] Wapedia, Works, a Wikipeida client, nice interface
[Free] Retro Clock (Widget): Sort of Works - The clock widget and the calendar work just fine (nice if you want a digital date/time display). The calendar widget opens the Google calender fine when pressed, but the clock does not open anything. This is likely due to the removal of the Alarm application and its integration into the Google Clock application.
Thanks to MisterSlanky for contributing.
Updated on 7-Jan-2010 at 7:50 PST
[Free] Handcent SMS works, great SMS application
[Free] Handcent Keyboard works, a good T9 IME for quick texting (still maintains voice input)
[Free] Battery Indicator works, a light weight task-bar icon that gives you battery %
[Pay ($0.99)] Advanced Task Manager: Works - Lets you manage active tasks and shut down all active tasks to help clear up memory/speed up the phone.
[Free] AK Notepad: Works - Very nice notepad application.
[Free] Amazon: Works - Gives full access and navigation to the store, wishlists, barcode scanning, and picture searches for items off of Amazon.
[Free] Astrid: Works - To-do list with flags to get things done, scheduling of to-do items, etc.
[Free] ASTRO: Works - File manager for the phone (one of my must-have apps)
[Free] Backgrounds: Works - Huge catalog of (non-live) backgrounds for the phone. Backgrounds look fine on the display.
[Free] Bump: Works - Contact information and file sharing application (cross-platform, files can be transfered to the iPhone).
[Free] Cestos: Works - Multi-player game much like marbles.
[Free] chompSMS: Works - Alternative to built-in SMS messenger. Does a better job with organizing the conversation visually.
[Free] Dial Zero: Works - Application to automatically make your way through phone trees to get to where you need to go (list is user-updated, so it's good, but not complete).
[Free] Documents to Go: Works - Read PDF, Word, etc. documents (pay version allows editing and Excel access).
[Free] Dolphin Browser: Works - Alternative brower that supports multi-touch pinch zooming and tabbed browsing.
[Pay ($0.99)] Doodledroid: Works - Android drawing application. Good to give kids to pass the time, or to pass notes when you want to draw out something.
[Free] Draw!: Works - Not as full-featured as Doodledroid; basic drawing application.
[Free] DroidDice: Works - Dice roller (d4-d100).
[Free] Google Sky Map: Works - Google's viewer that allows you to find constellations based on your current location.
[Free] Google Translate: Works - Basic Google translation service (many languages supported), also supports audio translation.
[Free] GPS Status: Works - Visual display of current access to GPS satellite to determine signal strength.
[Free] i Music: Works - Online music library download application.
[Pay? (I don't remember)] Keeper: Works - Secure password vault for the phone. Supports significant encryption and self-destructs after a number of failed login attempts.
[Free] Layar: Works - Use the camera + lists to find items using the camera as a visual interface.
[Free] Magic 8 Ball: Works - Really, it's just a magic 8 ball.
[Free] Metal Detector: Works (and wow it's more sensitive than my G1 ever was) - Detects metals using the built in magnetometer.
[Free] Mobile Banking: Works - Online banking application used by many banks to access account information.
[Free] Mobile Defense: Works - Application allows for tracking of your phone remotely from a website and the ability to permanently shut down the phone (not the SIM card) remotely.
[Free] Movies: Works - Flixter Movies lets you find theater show times, reviews, etc.
[Free] Open Table: Works - Restaurant reservation application.
[Free] Pandora: Works - Web based streaming music service.
[Pay ($0.99)] Power Manager: Works - Set up automatic features that turn on/off features and screen brightness based on current battery levels.
[Free] Ringdroid: Works - Create ringtones from MP3 files.
[Free] Sherpa: Works - Basic yellow pages application built into a map interface.
[Free] Shop Savvy: Works - Barcode/product search tool for finding prices of items on the web.
[Free] Solitaire: Works - Multiple solitaire games.
[Free] The Weather Channel: Works - Temperature, forecasts and radar images. (Yes I know it's built in, but sometimes I want radar)
[Free] Tiny Comics: Works - Database of current and upcoming comic releases searchable by publisher.
[Pay ($19.99)] Touchdown (Used 2.0 Build): Works - Full-featured MS Exchange syncing application. Syncs contacts, e-mail, calender, and to-do list. A must-have application if you use Exchange.
[Free] Trap!: Works - Simple game.
[Free] Word Up! (Free Version): Works - Word search game.
[Free] My Account: Works (Sort of, but yes it works). The application doesn't recognize the phone and provides an error message, but once you pass that message it works just fine giving information about minutes used, messages left, billing, etc.
[Free] Contact Owner: Works (Sort of) - Display selectable contact information on the lock screen in case the phone is lost (I put in my work address and phone number). This application works, but it kind of screws up your pattern login page. You have to fail the login once in order for it to scale back to full screen size. Workable, but a bit of a pain. An absolute must-have app.
[Free] Android Manager Free, Works, A task manager, application manager, and file manager
[Free] Barcode Scanner, Works, Scans QR and other codes and shopping services
[Free] City Caller ID, Works, Adds city and state of the incoming call
[Free] Goggles, Works, Take a picture, search based on the picture
[Free] Key Ring, Works, Keeps a copy of all your store discount cards/club (barcodes) so you won't have to carry them
[Free] T-Mobile Visual Voicemail, Works, the same as VVM from other devices
[Free] Wapedia, Works, a Wikipeida client, nice interface
[Free] Retro Clock (Widget): Sort of Works - The clock widget and the calendar work just fine (nice if you want a digital date/time display). The calendar widget opens the Google calender fine when pressed, but the clock does not open anything. This is likely due to the removal of the Alarm application and its integration into the Google Clock application.
Thanks to MisterSlanky for contributing.