[chris_overseas]

I've been using an Android app called "Mr Number" [1] for a few years now to help block nuisance calls. One of it's more useful features is its use of crowdsourcing to identify spam numbers and automatically block them right from the first time they try to call you. There's a bunch of other similar Android apps (presumably for iOS too?) that are worth a look too, depending on your particular needs. See the "Similar" section on the link below.

[1] https://play.google.com/store/apps/details?id=com.mrnumber.b...

[dredmorbius]

I'd used Mr. Number for a while, and even recommended it at one point. Its increasingly overreaching permissions demands, especially over contacts, lead me to drop it. I've since switched to a feature phone due to concerns with Android privacy generally, though my frustrations in not being able to screen or filter calls, on a whitelist basis, are high. Telephony generally is in desperate need of radical updating, with both control and privacy as major concerns.

[72deluxe]

Out of interest, what feature phone did you switch to?

[ajanuary]

iOS doesn't expose the necessary APIs to be able to filter calls.

[robin_reala]

Huh? What does Phone / Recents / ⓘ by the number that called you / Block this Caller do then?

Edit: oh, API for use by another app. Gotcha.

[geon]

iOS has that capability internally, obviously. But there's no API for 3:rd party apps to access that data, or to intercept calls.