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Scenario I usually take a train in the weekend and travel for 150 km with my Macbook or Tablet connected to my Android phone in tethering mode by bluetooth or wifi. While I travel by the train, my phone is usually inside my bag and I only have in front of me the Macbook... I check only sometimes the phone but it is mainly inside my bag. During my travel the phone connection change a lot and pass in one of this state: no connection, only phone network, 2G or 3G. What I'm searching to create is an app on the phone that talk with my macbook and regularly send information of the network state of the phone.
How should it work? These are the step for make it works:
I launch the apps on the phone that start the bluetooth server I launch the application on the mac that search for the bluetooth device around... than you are able to select the phone On the Mac menubar, an Icon display the state of the phone's connection: S = Setup, R = Network error, 2G slow connection o 3G Fast Connection. That's it for the moment..
What is available now? The application is in a alpha stage and buggy... @ 4 September 2012: The application on the phone work only the first time .. after that if you want to make it work again, you should restart the app. The application on the mac is working but it needs improvements too, as an example: It should make it possible to close it and leave only the menu bar icon. Tested with android jelly bean and a mac with osx snow leopard. For the moment I think it is a good example for understand how to make the phone and an application on a mac talks eachother with bluetooth.