How to stop annoying spam calls to your Android smartphone


Until recently, I thought unwanted spam calls were mostly a thing of the past. The Federal government, as well as many states, set up Do Not Call registries that allowed consumers to enter their phone numbers and block most undesired calls from companies trying to sell goods or services. There were hefty fines for repeated violations, so most companies played by the rules and families could finally enjoy a peaceful meal uninterrupted by telephone solicitors.

I was living in a fool’s paradise.

Technology has made it very simple (and very cheap) for unscrupulous companies to make thousands of calls at almost no cost to themselves, and when those calls are coming from outside of the U.S. it is almost impossible to enforce Do Not Call laws. As a result, the number of robot-dialed spam calls has exploded. It has also become simple to spoof numbers and make them appear as if they are coming from the same area as the recipient’s phone. These are especially insidious because for many people, the initial reaction is to think a local person or business is likely placing the call.

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Most carriers offer some sort of spam detection or filtering. If you are an AT&T, Sprint, Verizon or T-Mobile customer, you should be able to take advantage of your carrier’s spam filtering service. My informal survey of friends and colleagues suggests that none of these perform perfectly, but they do help cut down on the number of spam calls that you actually answer, both through filtering at the network level and alerting you to potential spam calls before you answer the call. 

Blocking spam calls via Google’s Project Fi

Let’s look at my personal carrier, Google’s Project Fi, as an example. My phone displays a red screen with a large “suspected spam” warning when Google determines that the incoming call is suspect. Users can also flag specific calls as spam to block additional calls from the same number, but since spammers change numbers very often, this feature is of limited usefulness. It still means you have to pull out your phone and take a peek to see the warning.

So while this is a step in the right direction, it isn’t quite there yet. As far as I know, there is nothing that shows how many, if any, calls are blocked at the network level, so it’s impossible for me to know how effective or ineffective network blocking actually is for Project Fi.

Apps that block spam calls

There are also some app solutions that are worthy of consideration.

Should I Answer? (free) depends on crowdsourcing by users to identify suspect telephone numbers. When a call comes in from a number that is not in your contact list, a rating will display that shows the number of negative reports that have been filed on that telephone number. You can choose to decline the call as well as report the telephone number of any spam calls you have received. The app also offers the very useful option to block all incoming calls from numbers that have been rated negatively or that have hidden numbers.

Another popular app is Truecaller (free) that works very differently from Should I Answer. Truecaller takes your all of your contacts and uploads them to the company’s servers. Since your contacts aren’t likely to be spammers, this is the basis for pretty effective filtering. On the downside, you just uploaded all of your contacts to a company’s servers. The risk of your contacts’ information being compromised in the event of a hack is more than just theoretical; it happened in 2013. I don’t feel it is ethical for me to share all of my contacts’ information without their consent, but if that isn’t a concern for you, Truecaller does do a decent job at identifying spam.    

There is no silver bullet that will currently eliminate all robot dialed spam calls, but an anti-spam app combined with carrier filtering can reduce their frequency. Also, even though it is not as effective as it used to be, registering your number with the Federal Do Not Call Registry will prevent calls from some telemarketers, so it is worth the minimal effort required.

Spam calls are an issue that has started to attract attention at a national level, so there is still hope that we can return to the days of dinner uninterrupted by unwanted telephone solicitations in the future.   

This article was written by Michael Connell from Computerworld and was legally licensed through the NewsCred publisher network. Please direct all licensing questions to