After using my Google Nexus One for a while now, here are some of the definite apps that one must have. Will update this list as and when I find useful & cool apps!

All the apps can be downloaded via the Android Market.

• Automatic Task Killer: Automatically kills persistent tasks that pop up when you screen is off. Reduces plenty of battery life.

Social Networking

• Seesmic: One of the best Twitter apps around. Seesmic just edges out Twidroid, which is also a fine app on its own for Twitter.
• Facebook for Android: Installed by default to access Facebook, what else?
• PingDroid: Uses the ping.fm service and is extremely useful for posting status updates to your Facebook & Twitter accounts simultaneously
• foursquare: foursquare is a location-based social networking service that allows you to check-in to the places you are at & find out where your friends are, what they are recommending and so forth.

Games

• Bebbled: Click to remove bubbles of the same colour!
• Jewels: This is the closest you can get to Bejeweled on Android. Absolute must have till Popcap realizes that Android users cannot be ignored.

I’m sorry I don’t have more games to recommend – gaming on phones have never been my thing… give me a proper controller anytime!

Music

• Shazam: Never ever knew what was that lovely tune you always hear on the radio? Shazam tells you what is the song; I’ve found countless classics with it!
• mSpot: Sharing your music library on the Cloud comes true with mSpot. Now you can bring your music out without even plugging your phone to your computer!