The best free spam call blocker app for Android

If you’re looking for a free spam-blocking app for your Android phone, the good news is that there are plenty. The bad news is that many (if not most) of them may actually make your spam problem worse. That’s because most of them share your data for advertising purposes or even have direct ties with data brokers. 

To help you choose the best option to block spam calls on your phone (without increasing spam elsewhere), we’ve looked at free spam-blocking Android apps in terms of user ratings, the features they offer, and how they handle user data. 

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NOTE: If you’re receiving a lot of spam, your personal information—like your phone number—may be for sale on data broker sites.

1) YouMail

Google Play store rating

4.3/5

Features

• Spam blocking: Automatically block spam calls and robocalls.
• Personal block list: Create a personal block list and add numbers you suspect belong to spammers.
• Call handling: Manage your voicemail with features such as voicemail to text and email, personalized voicemail greetings, and more.

Data privacy

Interestingly, the Google Play store states that YouMail shares no data with third parties. However, YouMail’s privacy policy states that they may share your data with the following third parties: 

• Advertisers
• Service providers
• Business partners
• Other companies not affiliated with YouMail.

On the other hand, the Google Play store discloses that YouMail may collect the following information:

• Name
• Email
• User IDs
• Phone number
• Photos and videos
• Voice and sound recordings
• Device and other IDs
• Contacts
• Messages
• App info and performance 
• App interactions.

On the plus side, YouMail encrypts all your data in transit, putting some measures in place to protect the data they process. They also provide users a way to request that YouMail delete their data.

2) T-Mobile Scam Shield

Google Play store rating

4.6/5

Features

• Scam blocking: Automatically block calls from scam likely numbers.
• Scam reporting: Report unwanted calls and add numbers to your personal block list.
• Caller ID: See who’s calling and decide if you want to answer.
• Allow list: Save numbers you don’t want to get blocked automatically.

Data privacy

Though the data safety section on Google Play states that this app doesn’t share any information with third-parties, T-mobile’s privacy policy states that they may share your data with them in some cases—primarily with service providers. These include data analytics providers, internet service providers, operating systems and platforms, and payment processors and financial institutions. 

That isn’t the only purpose they share your information for, however. The privacy policy also states that they share data with advertising networks and social networks for marketing purposes. 

The data safety section on the Google Play store also discloses that the only data the developer may collect is device and other IDs. However, this contradicts information found elsewhere, such as their privacy policy or the information provided on the App store for the iPhone version of Spam Shield, where it states that the app processes the following information:

• Name
• Email address
• User content
• Product interactions
• Customer support interactions

• Phone number
• Search history
• Device ID
• Crash data.

Another concern that raises some red flags for us is the fact that the app doesn’t provide any way to request they delete your data. 

3) Verizon Call Filter

Google Play store rating

4.7/5

Features

• Spam alerts: Receive alerts informing you of suspected spam callers along with the associated risk levels.
• Spam blocking: Automatically send high-risk spam calls to voicemail.
• Spam reporting: Report suspicious numbers.
• Filters: Select which types of incoming calls you want to block automatically.

Data privacy

Some of Verizon’s data-processing practices raise some red flags. According to the Google Play store, Call Filter only shares some of your messages with third parties for the purposes of app functionality, analytics, and account management. However, their privacy policy states that Verizon allows third-party advertisers to collect your data, combine it with information collected from other sources, and use that data to serve ads. 

While Verizon using your data to serve their own ads isn’t too alarming, the wording in their privacy policy implies that they may be sharing that data with advertisers, including (but notably not restricted to) Verizon, so that they can serve you targeted ads. 

According to the Google Play store, Call Filter collects the following data:

• Name
• Phone number
• App interactions and other user-generated content
• Messages
• Photos
• Device and other IDs.

Perhaps the most concerning part of the privacy policy is where Verizon admits they may be sharing some of your data for directories to publish, share, or use in other formats or for other purposes.  

On the upside, Verizon does allow you to remove your information from their database and provides encryption to protect it. 

4) AT&T ActiveArmor

Google Play store rating

4/5

Features

• Fraud-call blocking: Block numbers associated with fraudulent activity to prevent scam calls.
• Spam-call blocking: Block numbers that are likely to belong to spammers or send them straight to voicemail.
• Nuisance-call alerts: Receive alerts about telemarketing calls and other nuisance calls.
• Spam-call routing: Filter which categories of calls you want to receive, block, or send to voicemail.
• Unknown calls to voicemail: Automatically send incoming calls to voicemail if coming from numbers not saved to your contacts.
• Block all texts from email: Block all texts originating from emails.
• Spam-text filtering: Filter out malicious messages or texts from unknown senders.
• Personal block list: Create your own spam filter to block numbers automatically.
• Device security: Take advantage of features designed to keep your device secure.
• Breach reports: Receive alerts about the latest corporate data breaches.

Data privacy

Both AT&T’s privacy policy and the information available on Google Play’s data safety section indicate that they share some of your data with third parties. This includes affiliates, third-party advertisers, and service providers. 

According to the Google Play store, ActiveArmor shares:

• Phone number
• Contacts
• Device and other IDs
• App interactions
• Other user-generated content
• Other actions.

The information ActiveArmor collects includes:

• Name
• Email
• Phone number
• User IDs
• Contacts
• Approximate location 
• Precise location
• Web-browsing history
• App interactions
• Other user-generated content
• Other actions
• Other info. 

Unfortunately, like many similar apps, ActiveArmore doesn’t provide users any way to remove this information from their database. 

In terms of security practices, ActiveArmor encrypts data in transit and undergoes independent security reviews to ensure data safety. But it’s important to note that even the best security measures are no guarantee, which is what makes any spam-blocking app risky. 

AT&T experienced a massive data leak in April 2024 that affected millions of their users. The impact of this leak was so great that the FBI even had concerns that it may affect public safety and national security.

Choosing the best spam-blocking app for Android

There are several things you may want to consider when looking for the right spam-blocking app for your Android phone. It’s up to you which criteria hold the most weight when making your decision. For us, unsurprisingly, it’s data privacy. Coincidentally, it’s also the area most spam-blocking apps seem to be lacking in (hence our very short list). 

Here’s what we evaluated (and suggest you take into consideration):

1. Data privacy: We can’t stress how crucial it is to select an app that handles your personal information with care enough. Apps that have as much access to your personal information as spam-filtering apps should, by nature, have strong privacy policies, collect minimal data, and share as little of that data as possible. Apps with connections to data brokers or those that collect and share a large amount of data pose a higher risk to your privacy and security than spam.
2. Google Play store ratings: User satisfaction is usually a good indicator for how well the app blocks unwanted calls. Apps with many downloads and high ratings are generally more reliable in blocking spam.
3. Available features: All spam-blocking apps on our list perform the basic function of blocking spam. But many come with additional perks, such as customization options. Consider what extra features an app offers beyond basic spam blocking.

For many users, it may be best to go with the blocking tools that their cell service provider offers. This doesn’t have so much to do with how well they block unwanted calls, but rather the fact that it limits the exposure of your personal information. Whichever service provider you use likely already collects and shares your information. Using their app shouldn’t change that too much. Going with another app just creates another source of data exposure. 

Why spam-blocking apps may not be the best choice

Spam-blocking apps are typically pretty invasive. They have to be to effectively block unwanted calls. At the very least, they need access to your contacts, personal messages, and call logs. But just because it’s justifiable, it doesn’t mean it’s safe.

One of our main concerns is that many spam-blocking apps share your personal information with third-party advertisers—and not just for their own advertising purposes. While the number of unwanted calls may go down, this data sharing can actually increase the amount of spam you receive in your email, online messaging apps, social media, and even your physical mailbox. 

Not to mention that the more widely your information is shared, the higher the risk of data breaches, identity theft, and other security threats. Even apps from reputable developers aren’t immune to data breaches, as demonstrated by the data leak AT&T suffered. 

Downloading a spam-blocking app means putting a lot of faith in how it handles your personal information and how well it’s able to protect it. Because these apps are usually examples of proprietary software, you have limited visibility into how they actually do this. While they may claim to protect your information, there’s no foolproof way to verify these claims.

How to block all spam on your Android phone

Instead of downloading an app that blocks spam calls, we recommend an admittedly more time-consuming, but far safer approach. 

Here’s what you can do to block spam on your Android phone for free:

1. Sign up for the National Do Not Call registry to stop telemarketing calls, phone surveys, and other unwanted calls from legitimate callers. This won’t address scam calls or illegal robocalls, however. 
2. Block spam callers individually through your phone settings to stop repeat offenders.  
3. Block all unknown callers through your phone settings to prevent all spam calls (though this will block all calls from numbers not saved to your contacts).
4. Remove your phone number (and other personal information) from data brokers, including people search sites, to prevent spammers and scammers from finding it in the first place. 

For detailed, step-by-step instructions, see our guide on how to stop spam calls on an Android phone. 

More guides on stopping spam calls:

• How to stop spam calls on landline
• How to block a number on a landline
• How to stop spam risk (spam/scam likely) calls
• How to block restricted calls
• How to stop spam calls on iPhone
• What are “potential spam” calls? And how to stop them?
• How to block “No Caller ID” on an iPhone
• Got a call from yourself? How to stop it
• “No caller ID” vs “Unknown caller” and how to stop anonymous calls
• What is Dynata? Why are they calling?
• How to stop spam calls on iPhone
• How to stop robocalls
• Stop spam calls from health insurance companies
• Why are you getting so many spam calls?
• How to stop Medicare calls?

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