It's not supposed to disconnect. That's why they marketed it as an 'always on' device with the slogan 'online as it happens' and provide widgets that are dependent on a constant connection.

I'm not quite sure what you mean.. and I don't know about the N900 .. but on my G1 (android) if I am connected to WiFi it stays connected until I actually tell it to disconnect.....same for 3G.. it's "always on" 3G unless I tell it to use the smaller Edge network..

Otherwise.. it would have to constantly connect/disconnect every time I open up a new app that requires internet.. which would slow me down..

I would personally be kind of annoyed if my phone kept "guessing" for me when i wanted and didn't want the internet.... what if you have a widget or email app that updates a lot?

Wow, I've NEVER had a phone do that. Android, WinMo, iPhone/Touch/iPad? nope. They have inactivity timeouts, possibly, but instantly? Nope. Not for cellular data, and not for wifi.

Which device do you have that does that?

my most recent phone iphone 3gs disconnects from wifi as soon as I put it into standby. If you have a 3gs you can do this by putting it in standby/sleep while connected to wifi then wake it up. You'll see 3g for few seconds before reconnecting to available wifi thus saving battery.

I also had a N97 before the N900 and 3g connection would disconnect when I close the browser. While I was browsing I see a circular symbol with arrow indicating that I was using 3g/3.5g connection but as soon as I close the browser that symbol goes away but on the N900 it doesn't.

Does this make sense? I'm trying to find a way to automatically connect to network when I need but disconnect when I don't to optimize my battery life. I don't want a phone that is constantly connected and draining battery when I don't need to.

Your most recent phone iphone 3gs doesn't support Skype, Google Talk or you didn't switch it on. It is just one example why idea of automatic disconnection doesn't fly here.

When you put the iPhone into standby, it's far more powered down then the n900. This is a "feature" in apple marketing speak.

You can leave the 3g connected all the time, I do. No battery issues. Wifi, I'd go ahead and turn on/off as needed.

This would indicate activity.. not connection. Just like on my Android I get two little arrows, one up and one down, next to the 3G letters. When those are lit, I'm actually sending/transmitting data... when not it's idle.

The N900 would work this same way.. it just may not change the icon to show actual activity. In either case, you're always connected to the 3G, you're just not always sending and receiving data...

Never used an iPhone to know "standby" is... do you get phone calls in that mode? You'd have to be on 3G or EDGE to at least get phone calls.... a connection simply has to be maintained somewhere..

My n95 used to ask me whether I wanted to disconnect whenever I closed whatever was connected, so I wasn't 'online as it happens'. That's part of what I love about the n900 - no scrubbling for a connection. Just open the email/browser/app and I'm online. The n95 used to ask me which connection to use as soon as I opened something, which was a pain.

As a Nokia 5800 owner I have also noticed the same problem, the only option I have found is to disconnect wi-fi/3g each time I have finished using the web/email etc a bit time consuming/annoying but at least it means my battery lasts a full day now, rather than just until the late afternoon. I have also noticed all the apps on the phone continuously check the internet and so eat into my internet usage when I am away from my wi-fi connection.

Surely somebody could produce a simple app to disconnect when each app using the wi-fi/3g is closed?

Yuck, that's not what an always connected device is supposed to do though.