This story has been updated. It was originally published on August 23, 2019.

Your smartphone is a lot of things—a way to communicate with your loved ones, a tool to share your world, an occasional gaming console—but a vessel for ads and marketing campaigns should not be one of them.

Unfortunately, robocalls and spam calls are a serious problem for many of us, meaning we waste precious minutes fending off incoming calls we’re absolutely not interested in.

If you’re one of the approximately 328 million people who have received robocalls this year, know you can fight back with the help of your carrier, built-in options on your phone, or third-party apps.

Get a little help from your carrier

The AT&T Call Protect app, which can defend you against spam and robocalls.
AT&T’s Call Protect app for handling spam calls is available on Android and iOS. AT&T

Carriers aren’t all that fond of bots and spammers either, and usually offer strategies and tips for keeping them at bay. Thanks to a 2019 ruling from the Federal Communications Commission that says call-blocking tools can be opt-out rather than opt-in, your cell service provider can do more to protect you. The question, of course, is how much they’re actually doing.

AT&T was the first network to turn on automatic fraud blocking and spam call alerts for new users, and today it’s available to all users. You can also install the AT&T Call Protect app for Android and iOS, which will filter out unwanted calls and block specific numbers. If spam calls do get through, though, you can report them directly to AT&T.

[Related: The FCC is trying to crack down on those annoying spam texts]

Verizon customers, meanwhile, have access to Call Filter, a free app that comes pre-installed on Verizon-supplied Android phones and can be independently installed on iOS and other Android devices. The app warns you about potential spam calls as they come in and blocks suspected robocallers according to how aggressive you want to be with your filtering. You can report numbers via the app too, but to set up a personal block list, you’ll have to sign up for the $3-a-month Call Filter Plus service.

If you’re using T-Mobile, you’ve got a suite of tools to pick from. Scam ID is on your phone by default, and works with your device’s existing caller ID function to warn you if a call might be unwanted. On top of that, you can download the free Scam Shield app for Android and iOS to get more control over blocking specific numbers. Within the app, you can toggle on Scam Block, which will block suspicious calls before they get to you. There’s also Scam Shield Premium, which lets you send telemarketing and political calls directly to voicemail. The upgrade costs $4 a month, but it’s free if you’re enrolled in the Magenta Plus (from $85 per month).

You can also add yourself to the FCC’s National Do Not Call Registry. In theory, this should start stopping telemarketing calls 31 days after you sign up, but it won’t protect you against calls from political and charitable organizations, or scammers who choose to ignore the registry. You can also report unwanted calls directly to the FCC.

Use your phone’s built-in tools

A person sitting at a meeting, holding a Samsung phone with the Smart Call app that's alerting them of a spam call.
Samsung offers a built-in blocking option called Smart Call. Samsung

Both Android and iOS are getting better at blocking spammers and robocalls. Given the number of phone manufacturers that use different versions of the Android operating system, though, your device’s built-in options will depend on who made it.

Samsung phones have a feature called Smart Call, which might be on by default, depending on your carrier. If it’s not, just pick Caller ID and spam protection in Call Settings from Settings to turn it on. It will try to identify unwanted callers as they reach your phone, using a central database of suspect numbers. You can block and report numbers from right inside the app too, but it’s up to you whether you take or reject each call.

Google Pixel phones also have a built-in spam control feature. From the Phone app, tap the three dots in the top right, then choose Settings. On the next screen, pick Spam and Call Screen, and turn See caller & spam ID on. Google will subsequently attempt to warn you when it suspects an incoming call is spam. If you don’t want to decide whether to pick up each time, you can have it try to filter those calls out for you. You’re also able to block and report numbers from inside the app. If you don’t own a Pixel, you can still get the spam warning feature by downloading the Phone app onto whatever Android device you have.

Google also has Call Screen, a feature that lets you divert calls to the Google Assistant, giving the caller the option to leave a voicemail—quite a practical way of handling robocalls and spam calls. Call Screen works in the same Google Phone app, but it’s only currently available on Pixel phones and some other Android devices—you’ll see a Screen call option if you have it.

The Google Assistant using the Call Screen feature on an Android phone to stop a spam caller.
Why bother? Let Google Assistant pick up the phone for you. Google

On iOS, you can send unknown callers directly to voicemail. To set this up, open the Settings app, tap Phone, go to Silence Unknown Callers, and turn the toggle switch on. It’s smart, though, and won’t silence calls from any numbers it notices in your text messages or emails. However, you can only block numbers one at a time. To do so, tap the “i” button next to a number in your Recents list, then select Block this Caller. It’ll work for keeping ex-partners and stalkers away from you, but it’s not particularly effective for stopping a flood of spam calls and robocalls, which never seem to come from the same number.

Get some backup from third-party apps

The Hiya app for blocking spam calls on a phone.
Apps like Hiya flag unwanted calls as they arrive. Hiya

If the built-in tools in Android and iOS, plus the services offered by your carrier, are not getting the job done, several third-party apps can take on call-screening duties for you.

You may pause when wondering whether to give a third-party app access to your phone and your contacts list, and it’s a good idea to be wary whenever an app asks for any kind of permission. We contacted all the apps mentioned in this article, and they all assure us they aren’t raiding users contacts lists to build their database of spam numbers.

[Related: Here’s your checklist for maximum smartphone security]

If you’re not convinced, it’s worth checking out the privacy policies for the individual apps. For example, if you agree to share your contacts list with Hiya, the app will use this access to identify which callers you actually know, and they insist that information will not leave your phone.

All these apps work in a similar way, but there are differences worth mentioning.

First up is Hiya for Android and iOS. It checks incoming calls against its extensive database of trusted and untrusted numbers (Samsung’s Smart Call feature uses the same one) and tells you if a number is suspect. Hiya improves its database with information from its users, and you can help by reporting bad actors yourself. Pay $4 a month for the premium version and you’ll get access to a bigger, more frequently updated spammer database.

Nomorobo for Android and iOS will set you back $2 a month, though you can test it out free for 14 days. Again, it promises to identify spam calls and robocalls as they come in, using its own database and reports from users, but you’ll also have the choice to flag bad calls or block them completely. The developers of Nomorobo say the only blocked numbers are ones identified as illegal robocallers, so they promise the app will still allow “good” robocalls, such as ones from your kid’s school).

Another option is RoboKiller for Android and iOS. The app handles text message spam, too, and promises predictive spam call blocking technology, so it can identify and cut off calls even if the numbers aren’t in its database. RoboKiller takes a proactive approach, blocking calls and leaving you a notification so you don’t have to waste time making decisions every time someone calls. The service will set you back $4 a month, but you can test it out free for seven days.