When you don’t want to hand out your digits, don’t buy a separate phone. Burner apps let you create disposable phone numbers you can even reuse.

Decades ago, people changed their phone numbers all the time—if you had to move to a new town, you didn’t get to keep your number. Now, you can take your first cell phone number with you for life, even keeping the area code on a new continent if you’re willing to pay for it. That has downsides. Having another number associated with you for life, much like your social security number or driver’s license number, means it’s another easy thing for bad actors to use against you. Especially since your mobile phone number is likely associated with just about every digital account you have.

The way to get around that is to never hand out your personal phone number except to friends and family. There are a lot of good reasons for this. Perhaps you buy or sell items on Facebook Marketplace, manage an Airbnb listing, are hunting for a job, have a job that requires lots of phone calls, or you’re online dating. Give all of them a burner number.

Typically, a burner is a no-contract, prepaid mobile phone, usually an ultra-cheap handset you buy in a store (with cash, for privacy), activate with a call or online, use for a while, then discard. The throwing away is the “burning” part, but tossing it is optional, as the owner can “top off” the minutes on a prepaid phone and keep using it. With a burner, you don’t have to block a person (or stalker, shady marketer, or robo-caller) from your permanent phone. Nor do you need to get a new number.

For a second number, you can always get a prepaid SIM card on a cheap carrier if you want to go that route. Might even be handy if you have an extra phone around. And some new unlocked phones support eSIM standards where the SIM card that identifies you with the carrier is fully integrated and only changeable via remote software. But eSIM isn’t much of an option for a burner-style number. And swapping physical SIM cards to change phone numbers is a pain at best. Worse, dual-SIM phones are hard to come by (the Samsung Galaxy S21 FE and the quasi-smartphone Nokia 6300 4G being recent exceptions).

You already have a nice, expansive iPhone or Android smartphone that can’t handle two numbers, but you probably don’t want another handset. Thankfully, there are still many ways to get an extra, (possibly) temporary phone number that works with your smartphone (or even on your tablet, since most use some kind of Voice-over-IP system). The numbers can even be used to send and receive texts with photos.

This isn’t like using *67 or #31# before a call, which shows you as Blocked or Unknown. The services below make a point of displaying a temporary number when you call, so return calls can happen—until you want them to stop. If you just want the numbers to take calls, all the burner services feature things like voicemail and call forwarding.

There are some drawbacks to these burner apps and services. The biggest is that you typically can’t use them to call 911 for help. Some build that limit into their terms of service—they don’t want to get sued. Second, the companies behind some of these solutions have a very limited number of phone numbers to use. Research from 2014 found that some companies recycle numbers quickly, meaning you could be on the receiving end of calls you don’t want, from those trying to reach someone who previously had your number.

If you can overlook all that and still need a secondary number, get ready to access some apps and services that will maintain your privacy by becoming the number you hand out when you aren’t sure who to trust.