On their website,
Call Control says: "while we can’t guarantee we will block
every spam call, our cloud-based algorithms quickly identify
the worst offenders, dramatically reducing harassing and
In reality, that reduction turns out to only be stopping ~5%
of unwanted calls.
This is because scammers have access to hundreds of millions
of phone numbers. Which means that even a crowd-sourced
database will not come close to being enough.
imp stops 100% of unwanted calls because it checks for callers
you actually want to hear from. Everyone one else either
silently goes to voicemail or is blocked.