This is really great work, and it would be really cool to see this make it as a kit similar to the full size sim kit, and too see how much it would cost.

If possible the best interface would be to have a plugin to the existing comms/voip application on the device.

I have also wondered (but do not have the knowledge to poke around) whether some software exists to connect and use the built in Voip app on the N8x0s as a handsfree/dialler console connecting to a phone over bluetooth. I have used VOIP-VOIP over bluetooth and 3G, and it is reliable and robust.

We almost need something like an asterix server on the phone for the N8x0s VOIP client to connect to and route the calls out as a regular call, and when receiving calls to forward the calls onto the voip client on the tablet.
Heaven only knows if anything exists though.

blue_led, any progress?
I'm still checking this thread for updates every day and looking forward for your success, because i'm dreaming about doing the same with my tablet

google voice/grandcentral?

Actual stage is earpiece integration. I search for a small earpiece and I find one on nokia 2630 which also donated the antenna and mike. Placing this earpiece under front cover is a really hard problem because the place is very crowded and i must measure twice before cut so next update will be made after completing this job. Don't search thread daily.( this weekend I will go with my enduro bike on hills and next week I will go on easter vacation so i have limited time for this job)

For antenna I find a solution and will be placed inside speakers assembly. I have a small problem - finding thin coaxial cable ( 1mm ) for connecting the antenna.

i saw on schematics, uart3 have 2.8 V transceiver ( adapter ) so telit module can be wired directly on diagnostics pad

Sorry, but you missed the point Speculatrix. What would be needed would be a service on the phone which the Tablets VOIP client connected to, but then the phone service routes the call as a normal phone call. Like a bluetooth hands free service, but using the built in functionality.

And yes, I know a couple of bluetooth handsfree clients have been to the point of "almost works", and that we are not going to get anything now.

Anyways googlevoice etc don't work on this side of the water! (does it?)

BTW Blue_led - sorry for hijacking the thread for a moment, but heck, what you are doing impresses the hell out of me! Not a weekend project for the casual though I guess.

thanks for the update blue_led!
great work! can't wait to see it completed.

little step forward: L&G I proudly present .... hot from CNC machine .. front bezel drilled for earpiece

omg..... thats awesome....

this is a skilful and dedicated endeavour.
mad props blue_led your work is intricate and awesome.