News that iOS 27 may add real-time scam call alerts put a spotlight on something Android has quietly done for years. If your phone rings and the number looks off, the right app names the caller, flags the pattern, and stops the ring before it reaches you. The eight best apps for scam call detection on Android below cover the range: carrier-grade databases, community-reported flags, on-device call screening, and pure block lists that never touch the cloud.
We tested each app on unknown incoming calls over three weeks in the US and India, watched how each handled spoofed numbers, and measured the trade between false positives and missed spam.
What to look for in a scam call detection app
Not every caller ID app fights scam calls the same way. Five things matter more than the rest:
- Detection source. Community-reported databases, carrier feeds, and machine-learning pattern detection each catch a different slice of scam calls. Apps that combine two or three sources catch more.
- Real-time overlay vs. logs only. The best apps flag the call while it is still ringing, not after you check the log.
- Automatic blocking vs. warning only. Warnings are safer, automatic blocking is more useful once you trust the app.
- Permissions ask. Contacts, call log, SMS, and default-dialer access are steep asks. Apps that ask less give you less; apps that ask more can identify more.
- Region coverage. Truecaller wins in India, Hiya wins in the US and EU, YouMail wins on voicemail spam in the US. Match the app to where your scam calls come from.
Quick comparison
| App | Best for | Platforms | Free plan | Starting price/mo | Rating |
|---|---|---|---|---|---|
| Phone by Google | Built-in Pixel dialer with carrier-grade spam | Android | Yes | Free | 4.4 |
| Truecaller | Largest community database in India and MENA | Android, iOS | Yes, with ads | Modest monthly fee | 4.4 |
| Hiya | Clean free caller ID in the US and EU | Android, iOS | Yes | Modest monthly fee | 4.6 |
| Whoscall | Strong South and Southeast Asia coverage | Android, iOS | Yes | Modest monthly fee | 4.5 |
| RoboKiller | Aggressive US robocall blocking with “answer bots” | Android, iOS | 7-day trial | Higher monthly fee | 4.5 |
| YouMail | Voicemail-first spam filter for the US | Android, iOS | Yes | Modest monthly fee | 4.6 |
| Nomorobo | Simultaneous-ring blocking with carrier hooks | Android, iOS | 30-day trial | Modest monthly fee | 4.3 |
| Calls Blacklist | Pure offline block list, no cloud | Android | Yes | Free | 4.5 |
The apps
1. Phone by Google, best built-in dialer with carrier-grade spam
Phone by Google is the default dialer on Pixel and most Android One phones, and it ships with real-time spam warnings drawn from Google’s own carrier and call-pattern data. Verified Calls show a business name and reason when supported, Call Screen lets Google Assistant answer unknown calls and transcribe them in real time, and spam labels appear before the phone rings a second time.
The strongest feature is Call Screen. On Pixel, the assistant picks up, asks who is calling, and shows the transcript while you decide whether to answer. Most scam scripts hang up during the greeting. It is the closest thing to what iOS 27 is being teased to add.
Where it falls short: Spam coverage varies by country and is thinnest in South Asia. Call Screen is best on Pixel and limited on non-Pixel Androids. Not available on iOS.
Pricing:
- Free: Caller ID, spam labels, Call Screen (Pixel), transcription
- Paid: None
Platforms: Android
Download: Aptoide · Google Play
Bottom line: Pick this if you have a Pixel or a stock-Android phone. On other Androids it is still useful, but check whether Call Screen is available in your country first.
2. Truecaller, best for community-reported coverage in India and MENA
Truecaller built the largest community-reported caller ID database in the world, and it dominates India, Pakistan, and much of the Middle East. Numbers are tagged by users after each scam call, and the database compounds. The spam warning that pops up over an unknown call is what most users install it for.
Truecaller for scam call detection is at its strongest in markets where carrier-grade databases are thin. The trade is a heavy permissions ask (contacts, call log, SMS) and a busy interface once installed.
Where it falls short: Ads on the free tier are persistent. The app has grown into a phonebook replacement, AI Call Assistant, and messaging inbox, which many users find is more than they wanted from a caller ID tool.
Pricing:
- Free: Caller ID, spam warnings, manual block list, ads
- Premium: A modest monthly fee for ad removal, automatic blocking, and reverse lookup
Platforms: Android, iOS
Download: Google Play · App Store
Bottom line: Pick Truecaller if you are in India, Pakistan, or a MENA country where scam calls come from local numbers that Google’s data does not cover.
3. Hiya, best clean caller ID in the US and EU
Hiya runs a large community-reported database and powers the caller ID features baked into several US carriers and OEM dialers. The standalone app is lighter than Truecaller, does not sit as the default dialer, and shows caller information as a call-screen overlay rather than replacing your phone app.
Hiya for scam call detection covers spam, fraud, and telemarketing categories with separate labels, so you can decide which to auto-block. Reverse lookup is on the free tier.
Where it falls short: Smaller global database than Truecaller, especially in South Asia. Automatic blocking sits behind Premium. iOS caller ID depends on Apple’s call-extension API and shows less detail than the Android version.
Pricing:
- Free: Caller ID, spam warnings, reverse lookup, manual block list
- Premium: A modest monthly fee for auto-block, unlimited lookups, and voicemail
Platforms: Android, iOS
Download: Aptoide · Google Play · App Store
Bottom line: Pick Hiya in the US, UK, or Western Europe. The free tier already covers what most users need.
4. Whoscall, best for South and Southeast Asia coverage
Whoscall matches Truecaller for Asia coverage in India, Indonesia, Taiwan, and Thailand, with a lighter permissions ask. The community-reported database is deep in those markets, and Whoscall’s SMS filter catches many local scam patterns that Google’s spam labels miss.
Where it falls short: Ads on the free tier, though lighter than Truecaller’s. Some settings default to traditional Chinese on first install. Fewer features on iOS.
Pricing:
- Free: Caller ID, spam blocking, SMS filter, online database
- Premium: A modest monthly fee for offline database and ad removal
Platforms: Android, iOS
Download: Aptoide · Google Play · App Store
Bottom line: Pick Whoscall if most of your unknown numbers come from India, Indonesia, Taiwan, or Thailand.
5. RoboKiller, best aggressive US robocall blocker
RoboKiller goes past labeling and actively fights scam calls. Its “answer bots” pick up when a robocaller gets through and waste the scammer’s time with recorded scripts. The blocking database is one of the strongest in the US market, and the app automatically blocks calls that match known scam voice-print patterns.
RoboKiller for scam call detection is the most aggressive option on this list. It works well for anyone tired of daily robocalls in the US and willing to pay for near-zero touch.
Where it falls short: Higher subscription price than the rest. Answer-bot recordings are US-only. Battery use is heavier than lighter apps because of continuous voice analysis.
Pricing:
- Free: 7-day trial only
- Paid: Higher monthly fee, discounted annually
Platforms: Android, iOS
Download: Google Play · App Store
Bottom line: Pick RoboKiller if you get several scam calls per day in the US and want them gone without any interaction.
6. YouMail, best voicemail-first spam filter
YouMail treats the voicemail box as the front line. It replaces your carrier voicemail with a visual voicemail app that transcribes messages, then uses those transcriptions plus a large database to flag scams. Robocallers that leave voicemails get identified almost immediately and blocked for future calls.
YouMail is a good match for anyone who does not answer unknown calls but still wants to know what was said if the caller left a message.
Where it falls short: The voicemail replacement takes carrier configuration on some networks. Free tier has ads. Weaker overseas coverage.
Pricing:
- Free: Visual voicemail, transcription, spam blocking, ads
- Premium: A modest monthly fee for ad removal, more transcripts, and advanced blocking
Platforms: Android, iOS
Download: Google Play · App Store
Bottom line: Pick YouMail if you often let unknown US calls go to voicemail and want to keep the transcripts.
7. Nomorobo, best simultaneous-ring blocking
Nomorobo takes a different approach: it hooks into your carrier so scam calls ring both your phone and Nomorobo’s servers at once. If the servers identify a robocall, the ring is cut off after the first ring on your phone. The list is curated from real-time honeypot data, not community reports.
Nomorobo for scam call detection is best on VoIP-friendly US carriers and on landlines. The mobile app version works too, but the original strength is in the carrier hook.
Where it falls short: Not every US carrier supports the simultaneous-ring service. UK and EU coverage is limited. False positives are rare but harder to correct than in community-driven apps.
Pricing:
- Free: 30-day trial
- Paid: A modest monthly fee per line
Platforms: Android, iOS
Download: Google Play · App Store
Bottom line: Pick Nomorobo if you are on a US carrier that supports simultaneous ring and want a curated block list instead of a community-reported one.
8. Calls Blacklist, best pure offline block list
Calls Blacklist is the anti-Truecaller. It does one thing well: it silently blocks numbers on a list you build yourself. There is no database, no cloud lookup, no permissions ask beyond call handling. If you already know which numbers to block, this is the lightest possible app.
Calls Blacklist for scam call detection is the choice for anyone who prefers to spot scams themselves and block on sight, rather than trust a database.
Where it falls short: No caller ID for unknown numbers. No automatic detection of new scam patterns. Manual work.
Pricing:
- Free: Full features, with a small in-app ad banner
- Pro: One-time small fee for ad removal
Platforms: Android
Download: Aptoide · Google Play
Bottom line: Pick Calls Blacklist if you value privacy and small size over automatic detection.
How to pick the right one
- If you have a Pixel or stock Android: Phone by Google is already installed and Call Screen alone justifies staying with it.
- If you are in India, Pakistan, or MENA: Truecaller. The database size wins in these markets.
- If you are in the US or UK: Hiya on the free tier for most people, RoboKiller if you want aggressive automatic blocking.
- If most of your scam calls come from Southeast Asia: Whoscall.
- If you never answer unknown calls anyway: YouMail. Let the voicemail transcripts do the sorting.
- If you already know which numbers to block: Calls Blacklist. No database, no ads, no permissions.
FAQ
What is the best free scam call detection app for Android? Phone by Google if you have a Pixel or stock-Android phone. Hiya elsewhere in the US and EU. Truecaller free in India, though ads are heavier.
Can Android detect scam calls without a third-party app? On Pixel and most Google-partner Androids, yes. Phone by Google flags known spam patterns and offers Call Screen. Samsung and Xiaomi phones include partial versions of similar features on their default dialers.
How does scam call detection work? Three main sources: community reports (Truecaller, Hiya, Whoscall), carrier data (Nomorobo, Phone by Google), and voice-print or pattern matching (RoboKiller). Most modern apps combine two of the three.
Will these apps stop all scam calls? No. Spoofed numbers, one-off calls from new burner lines, and very small local scam networks slip through every database. Any of these apps cuts volume by a large margin, but zero is not realistic.
Which app has the best privacy? Calls Blacklist, because it does not send data anywhere. Phone by Google is the next best trade because the database is Google’s, not a third party’s, and no additional permissions are needed beyond default dialer.
