[auraham]

I have searched for a project for blocking robocallers using a Raspberry Pi. Recently, I have received a lot of annoying calls on my landline phone. Surprisingly, there is a lack for solutions based on Raspberry Pi. This project [0] seems to be the best for the task. However, you still need to invest on a USB modem. The author recommends a U.S. Robotics 5637 Modem, but it is expensive, at least in Mexico. Compared to blocking ads with a Pi Hole, blocking robocallers is harder.

[0] https://emxsys.github.io/callattendant/

[flarg]

Kind of like what Android does already?

[auraham]

Yes. There are many apps that work for mobile phones. There are also some devices that block calls using a landline phone. However, they are not flexible. If you want to block phone numbers using a pattern, like *01 to *99, it is difficult to do it using those devices. That is why a Raspberry Pi would be a better fit. However, it seems to be more expensive.