Telephone scammers and spammers don't care whether they call a landline or wireless phone. And they don't give a hoot if that number is on the federal Do Not Call List. They're just looking for someone to rip off.
"It's just ridiculous," said Keith Turner of New York, who pays his wireless company a dollar a month for its call-blocking service. "If I didn't block these bogus calls, I'd literally be on the phone all day."
Many of us with cellphones feel harassed by nuisance calls and we're not happy about it. The Federal Communications Commission received more than 16,500 complaints about unwanted—and most likely illegal—calls and texts to wireless devices in just the first three months of this year. And the problem is only going to get worse as the shift continues from landline to mobile phones.
There are dozens of free apps available in the Google Play store that let you screen your calls, alert you to potential fraud and even block suspected voice and text message spam. These services, such as Truecaller, PrivacyStar and WhitePages Current, use crowd-sourcing—reports from their users—along with information from public databases and their own algorithms to detect unwanted calls.
"When your phone rings and you have to decide whether to answer or not, we try to help you figure out who's calling and why," said Jonathan Sasse, CMO of PrivacyStar.
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PrivacyStar uses a color-coded system to signal who is calling:
- Green: A caller who is not your address book and is not known to be a telemarketer or debt collector.
- Yellow: A known telemarketer or debt collector.
- Red: A telemarketer or debt collector on PrivacyStar's list of reported offenders.
In the case of suspected fraud, the call is blocked automatically and the user gets a blocked call alert. The PrivacyStar app also makes it possible for you to block a number that you don't want to hear again, which would also stop any text messages from that number.
Richard Palazzolo, who lives in San Francisco, says the PrivacyStar app works very well.
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"I seldom get nuisance calls anymore, and when I do, I just block them," he said.
The Truecaller app, developed by a company in Sweden, has been downloaded by more than 64 million people around the world. The company says it blocks more than 5 million spam calls every day.
"As the call comes in, you will see immediately if this is an unwanted call that's been reported as spam," Truecaller CEO Alan Mamedi said from Stockholm.
The app can be set to automatically block calls with a high spam score. These calls won't make your phone ring. Instead, you'll get a silent message that shows the number of the blocked call, the name (if they have it) and the spam score. Text messages from suspected spammers will be moved to a spam inbox, similar to what happens with email. The app will also warn that it's probably fraudulent.
Dayna Wolchko, who lives near Cleveland, said she used to get four or five nuisance calls a day. She decided to give Truecaller a try and she loves it.
"It's amazing," Wolchko said. "Those unwanted calls stopped right away."
These apps can also warn users about known scams and help protect them from fraudsters. The WhitePages Current ID app alerts its users to the costly one-ring scam perpetrated by crooks in the Caribbean.
This scam, which CNBC warned about earlier this year, is deviously simple. The phone crooks simply call from Jamaica or Antigua or Barbados and hang up right away. They hope you will see the number in your missed calls log and be curious enough to call it back—not realizing this is an international pay-per-call phone number that charges you $9.95 as soon as you connect.
"We have more than 22,000 numbers in our database that are related to this fraud," said Tom Donlea, director of risk services at WhitePages. "Incoming caller ID gives you a warning that says this is a fraud or possible scam. If you miss the call, which is what they want, and you return it, you will also get the fraud alert message. That way you can hang up before you incur a charge."
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In San Diego, Gabe Cooley downloaded the WhitePages app after he was targeted by telephone scammers.
"It's pretty neat," he said. "It tells me where the call is really coming from and if I see it's from Jamaica, I'm not going to answer it."
All three of these apps are free on Android. The companies hope you will like them enough to upgrade to their premium services.
Android & Apple
Google play rating: 4.1 (12,400 reviews)
Android, Apple, Blackberry, Microsoft
Google play rating: 4.3 (665,500 reviews)
Android
Google play rating: 4.4 (181,300 reviews)
—By CNBC contributor Herb Weisbaum. Follow him on Facebook and Twitter @TheConsumerman or visit The ConsumerMan website.