8x more accelerated
6x less disk, CPU, and
You probably love your smartphone – except for maybe the phone part and, in particular, the telemarketers often on the other end of the line. Telemarketers make 148 million annoying, time-wasting calls per day1 and do-not-call lists (where available) do not work2, 3 (and weren’t even meant to for many types of telemarketers4). Callblock is the first iOS app that helps prevent these calls.5
Based on our benchmarking, the app identifies 86.7 percent of telemarketing calls correctly with only 1.7 percent false positives on average.6
Callblock is something of a sequel to our ad blocker, Adblock Fast, which has 750,000 users and is rated 4.5 and 4 stars in the App Store and Google Play since launching alongside iOS 9 then the Samsung Galaxy S6. We’ve built on our experience filtering online advertisers to compile, classify, and apply what we think is the world’s biggest directory of telemarketers, featuring millions of entries from almost every country in the world.
With the app, you can:
- Filtering ruleset
- Install filesize
- Page load time
- Peak CPU use
- Peak memory use
- 49,002 rules 49K rules
- 843 KB
- 162.5 MB
- Adblock Fast
- 7 rules
- 97 KB
- 58.5 MB
- Adblock Plus ABP
- 49,002 rules 49K rules
- 543 KB
- 158.0 MB
1. Reduce telemarketing calls an average of over 85 percent.
2. Block calls from over 3,000,000 telemarketers by type.
3. Add and report missing or misclassified telemarketers.
4. Just tap to caller-ID only rather than block telemarketers.
- Facts and figures on telemarketing, The Houston Chronicle, accessed September 6, 2016.
- Cutting off robocalls, The Federal Communications Commission, accessed September 6, 2016.
- Do-not-call list “useless”, critics say, The Canadian Press, accessed September 6, 2016.
- Who may or may not call?, The Federal Trade Commission, accessed September 6, 2016.
- Callblock’s new iOS app will block calls, TechCrunch, accessed September 7, 2016.
- Calls were sampled and Callblock’s identification of telemarketers, evaluated in May 2017.
Show or hide the raw benchmark data.
Callblock blocks unwanted telephone calls not iMessage, SMS, or MMS messages. To allow the app to block calls:
- press the Home button on your iPhone,
- tap the Settings app,
- tap Phone > (under CALLS) Call Blocking & Identification, then
- toggle the Callblock switch on.
To unblock calls, navigate to the Callblock app. To add or remove a missing or misclassified caller, tap the Add caller button.
Enabling Callblock or making changes in the app may take up to a minute to take effect.
Questions, possibly to be asked frequently
Who created Callblock?
What are Unclassified callers in Callblock?
Unclassified callers are those we’ve identified as telemarketers but not yet which type.
Which countries does Callblock work in?
Callblock can screen telephone calls from almost every country in the world – 174 of the 193 recognized by the United Nations and so many that naming which countries are not supported is a whole lot easier. They are:
The Dominican Republic
The Marshall Islands
Saint Kitts and Nevis
Trinidad and Tobago
The countries Callblock supports are:
Bosnia and Herzegovina
The Central African Republic
The Czech Republic
The Ivory Coast
Papua New Guinea
Sao Tome and Principe
The Solomon Islands
The United Arab Emirates
The United Kingdom
The United States
Where does Callblock list blocked calls?
Callblock can’t monitor your incoming calls (to list or do otherwise with them) due to iOS’s privacy model. Blocked calls are sent straight to voicemail. You may want to set the app to caller-ID only till you’re comfortable the right callers are being screened out.
When will Callblock be available on [insert platform here]?
Callblock is available for iOS 10 (on 64-bit phones, iPhone 5s and up). Subscribe to be notified when versions for other platforms become available.
Why is a subscription required if Callblock was purchased?
You don’t need a subscription if you bought the first version of Callblock, but later versions can’t determine whether you bought the first version if you’ve since deleted the app. Forward your App Store receipt to firstname.lastname@example.org, though, and we can credit you with a subscription.
How is Callblock’s directory of telemarketers compiled?
Callblock’s directory comes from public and private records, the results of our ongoing research and testing, and user reports. Over 10,000 new entries on average are added to the directory and existing entries, reclassified daily. The app autoupdates to include these changes.
How can a subscription be canceled?
Apple manages subscriptions in iOS (not developers, like us). See their instructions for accessing your subscriptions.
How much does Callblock cost?
You can try Callblock free for a month. Afterwards, the app is $1.99 monthly or $19.99 yearly.
Are Unknown callers blocked by Callblock?
Callblock can’t block any call without a caller ID. This is an iOS limitation, but most telemarketers don’t block their caller IDs.
Does Callblock require Contacts access?
Unlike similar apps, Callblock doesn’t need to access your Contacts to work.
Can a missing or misclassified caller be added or removed?
To add or remove a missing or misclassified caller to or from Callblock’s (local) directory (and to report the caller for review to help improve the distributed directory), tap the Add caller button, enter the caller’s telephone number, and choose which type the caller is or the Not a telemarketer option if the caller isn’t a telemarketer.