NexusSpam call blockers compared with AI call screening
Spam blockers check a caller's number against lists of known spam, then block it, label it or send it to voicemail. AI call screening answers the call and asks who's calling and why, so it can also catch scams from new or faked numbers.
How spam blockers work
Spam blockers come from your phone company, your phone's maker and app makers. The FTC says blocking apps use call data and reports from users, the FTC and other sources to predict which calls are likely scams. Then they block the call, label it as spam or send it to voicemail.
Many phone companies offer these tools. Some are free and some cost extra, so check with your carrier.
On Android phones that use the Google Phone app, caller ID and spam protection is on by default. It warns you about suspected spam, and a Filter spam calls setting keeps those calls from ringing.
Many phones let you block calls from specific numbers. On iPhone, you can also set unknown callers to Silence, which sends them to voicemail.
What blockers do well
They're simple, often free, and work in the background once turned on.
They work best on numbers that have already been reported or flagged, and they add no extra step for the people calling you.
Where blockers fall short
Scammers can make any number show on caller ID. A brand-new or faked number may not be on any list yet. The FTC notes that not all scam calls get flagged.
Blockers can also catch calls you want. The FTC warns that blocking services might block some wanted calls, and Google says calls from people you know can be mislabeled as spam.
Silencing every unknown caller also silences the new doctor's office calling back, so you have to remember to check voicemail.
How AI call screening works
Call screening answers calls from unknown numbers before your phone rings. An assistant asks who's calling and why. Based on the answer, the call rings through, goes to voicemail or is stopped.
Recent versions of iPhone software have this built in. Go to Settings, then Apps, then Phone, and under Screen Unknown Callers choose Ask Reason for Calling.
Google Pixel phones in the US and some other countries have Call Screen, which can answer for you, ask who's calling and why, and hang up on spam. Google says it works on the phone itself, and that not all spam calls and robocalls can be detected.
Services like Nexus answer for you through call forwarding, so they can work on both iPhone and Android.
What screening does well, and its trade-offs
Screening listens to what the caller says, not just the number. That helps with scams from new or faked numbers. You also learn who called and why.
The trade-off is that callers you don't know have to answer a question first. Saving the numbers of offices that call you, like your pharmacy or doctor, in your contacts lets them ring straight through. Screening can also get a call wrong, so glance at your call history now and then.
Which is right for you?
If you get a few spam calls and don't mind unknown numbers going to voicemail, the free tools on your phone and from your carrier may be all you need.
If you or a parent pick up every call, or scams keep coming from numbers that look local, screening adds a check before the phone rings. You can also use both.
How Nexus handles it
Nexus is AI call screening that works through call forwarding to a separate Nexus number, which is included. You keep your own phone number and carrier. It works on Android and iPhone. On Android, you install the app from the Nexus website rather than Google Play.
People in your contacts always ring and are never blocked. Numbers on the spam list are refused, and most callers you don't know are asked who they are before your phone rings. An automated assistant asks who's calling and why, and callers are told the call is being screened and may be transcribed. Anthropic's Claude reads what they say. Real callers are put through or leave a voicemail you can read as text. Calls with no caller ID are refused.
Nexus also keeps a shared block list, like a spam blocker. A number caught as spam on more than one member's line, plus numbers from public FTC complaints, is blocked for everyone. Only the number is shared, never what was said. The person running the service can't read your voicemail or hear what callers said. More about how it works is on the About page.
Nexus is invite-only. The price is on the wait list page, and you can cancel yourself any time.
Common questions
Are free spam call blockers good enough?
For many people, yes. They do well with known spam numbers, and many are free. They can miss scams from new or faked numbers, and sometimes block a call you wanted.
Can I use a spam blocker and call screening together?
Often, yes, but check how they work together. For example, Google advises not using Pixel's automatic Call Screen if you use call forwarding, because screened calls won't be forwarded.
Does Nexus block spam texts?
No. Nexus screens phone calls only. Use your phone's own settings for spam texts.
Sources
Last updated 2026-11-09. This page is general information, not legal or financial advice. To report a scam, visit reportfraud.ftc.gov.