Hi.

Been searching for quite long for full-duplex walkie-talkie, but don't seem to find any, at least citizen ones.
An idea came up to me in those Windows Mobile years, which could at last be (probably) done on N900.

The reason is quite simple. I enjoy cycling and chatting with a friend of mine. However, that's quite difficult (and dangerous) in a city, since you have to cycle very close to each other to be heard over ambient city noise.
Now another friend bought a bike and joined us, so the probem got even more complicated.

Each of us has a wifi/bt enabled phone - two n900 and one nokia 5800. I would like use the bt or wifi capability to join up the devices in one network and use headsets for full-duplex communicating in some VoIP application.
Here comes the questions.

1) Bluetooth or wifi? The range is only about 15meters max, so BT should do. I guess WIFI power consumption is greater than BT. However, you won't be able to use a BT headset then. Not a big deal, as wifi+gsm+bt (and probably gps) would drain the battery in no time.

2) Since there're three of us,AdHoc won't do. One of the devices must be in AP mode to accept two connections. Can it be done for BT out of the box? Is there're a WiFi AP for n900, supporting multiple clients?

3) Which VoIP aplication doesn't require a server or other CPU-intensive appications to work? A very light local p2p application is needed, whith clients available for at least Maemo and Symbian.

4) Battery life. That is the major issue. The whole system have to be online for at least 3 hours, and leaving enough juice for a 1hr standby during way back home.

Here is an old but interesting idea:

http://talk.maemo.org/showthread.php?t=23120

Ogh, bonjour should do. Does the n900 and 5800 have applications supporting voice conferencing over bonjour?

Adhoc support more than 2 devices

I'd like something similar as well. Though in my case I'd like to see an app for s40 and s60 and n900... I would find this very useful for shoping for when there are queues to stand in and people split up then they can coordinate what do buy without the need of yelling or deciding on things ahead of time to much.