While in a call it will switch automatically between speaker and head output based on the values from proximity sensor.
This will only work if you have a phone with proximity sensor hardware like the nexus, Desire, Samsung Galaxy S, G2, DroidX.
If it doesn't work on your phone, please contact me by mail
+ sensor calibration
You can get the apk from the project site for free including the sourcecode, this is just a donate version.
If you send me a error log, please write what you have done and what happend.
+ Added finish translation
+ Added quickfix for proximity issue where screen off sensing continued when the app got killed during a call
Just deactivate the second checkbox with "handle screen off" in the settings screen.
I'm still investigating into this and will fix it as soon as I find a solution to it.