Advanced Call Manager Free lets you stop unwanted calls getting through to you - without having to 'red button' the caller.
Using the free version of Advanced Call Manager, you can instruct your phone to reject all calls, or only allow calls from numbers in your phone contacts. There's also an option for automatically rejecting calls from hidden numbers.
When Advanced Call Manager rejects a call, the person who is calling will hear the busy tone. This, therefore is a more polite way of telling them to go away than to just hit the red button to cancel the call and play the cut-off tone.
Advanced Call Manager is very effective at what it does, is easy to configure, and runs quietly in the background once activated. Lots of the more interesting features from the full version of Advanced Call Manager are unavailable in this free version (SMS replies, call diversion, caller black and white lists), and the functionality therefore feels very limited.
But if you're looking for a simple way to discreetly block unwanted calls, Advanced Call Manager Free does a decent job.