Icons
Nexus One Icons & what they mean

Add/remove widgets
To add:

• Press the Home button
• Select Menu > Add > Widget

To remove: Select and hold then widget, drag it to the trash can that appears where the application window was.

Optimize Battery Life

• Press the Home button > Menu
• Select Add > Widgets > Power Control
  This Widget will easily allow you to turn off services that drain battery, like Wi-fi, Bluetooth, Screen briteness, e-mail and facebook sync, and GPS

Import contacts
From SD card:

• Insert SD card with vCard file (in root)
• Go to Contacts > Menu > Import/Export > Import from SD card

Watch Youtube Videos in high resolution
When watching a video select Menu > More > Watch in high quality

Viewing Notifications
Simply touch the top status bar and slide down

Pairing a Bluetooth Headset

• Press the Home button > Menu
• Go to Settings > Wireless & Networks > Bluetooth > Bluetooth settings
• Put your headset in pairing mode
• Select Scan for devices
• Your headset should come up in the list – if there’s a password, enter it (probably 0000)
• You should now be able to connect to the headset

Switch applications/recently used
Simply hold down the Menu key

Delete a single call or message
Select the message or call you want to delete and hold – a window of options will pop up and you can select ‘delete’.

Delete a bookmark
Long press the bookmark and select Delete bookmark

Save a picture
Save pictures (MMS or browser) by long pressing them. An option to save will appear.

Load files from your computer

• Connect your N1 to your computer using provided USB cable
• Go to Notifications by touching the top status bar and sliding down
• Select USB Connected
• Notification > Select Mount
• You should now see the N1 as a drive in explorer or finder
• When you’re done moving files, go to Notifications and select Turn off USB storage

Set audio file/mp3 as ringtone
Open the file you want to set as a ringtone in the media player – click the menu – set as ringtone

Set ringtones per contact
Go to Contacts – Select a contact – Select Menu > Options – Under ringtone choose the ringtone you’d like to set for this person.

Set tones per Notification
If you go to the individual application that you want to set the notification for you can change it there under the menu.
For example. Click on Messaging > Menu > Settings – scroll down to Notifications – there is a setting for ringtone or vibrate. (same steps for e-mail and Facebook)

Save word to dictionary
While typing – when a word comes up, longpress it. It will be added to the dictionary

Speed Dial

• Long press on the home screen to bring up the shortcut menu
• Select Shortcuts
• Select Direct dial
• Select the contact you want
• You’re done!
• You might want to move the direct dial to another screen to prevent accidentally dialing that person

Copy/Paste

• In any text field – long press
• Edit text will appear
• Cut all and Copy all will be among the options.
• If you have something on the clipboard Paste will be an option

Lock a Text Message

• Go to Messaging
• Open a conversation
• longpress an individual text message – an option will appear to Lock message
• to unlock long press the locked message and select Unlock message

Stop Running Applications

• Select Settings
• Applications
• Running services
• Select the desired service
• Stop

Safe Mode

• With the phone off, slide open the keyboard open
• Press and hold the Power+Menu button (on the keyboard)
• Continue to hold until the boot screen comes up and you feel the phone vibrate
• Phone should start up and say “Safe Mode” in the bottom left-hand corner
• Explanation – This starts only the core Android processes. This is best used for diagnosing if a 3rd party application is causing your phone to malfunction or if you cannot uninstall if when in regular mode.
• TRY THIS FIRST if you are having any problems with your phone acting up, especially with the built-in Android apps (example – Messaging app is crashing. Boot in Safe Mode. If app doesn’t crash when doing what you were doing in regular mode, it’s most likely going to be a 3rd party app with access to messaging that is causing a problem.)
• BE AWARE that after coming out of Safe Mode, 3rd party widgets might not display properly on the home screen. Press and hold on the widget and drag it down into the trash can, then readd it to the home screen. This will fix the “problem loading widget” error.

Source: Cellphoneforums