Happy to talk about the landline product. Just for clarification, the mobile product works completely differently.

1. Yes, pretty much. Here's a more in-depth answer to what happens when the call is answered - http://www.6083716666.com/

2. Yes, we do get a log of the incoming calls. We use that to analyze the high frequency calling patterns across millions of phone lines and build the blacklist. The more people that contribute, the better the algorithm gets.

3. We globally manage the whitelist and good robocalls (school closings, pharmacies, doctors offices, etc)

4. We don't work with POTS lines yet. The older technologies are tougher to protect than the modern ones.