Over 20 million devices have downloaded a new class of activity tracking apps that have recently experienced enormous success on Google Play, the official app store for Android.

The apps advertise themselves as fitness, pedometer, and habit-building aids, promising to award users randomly for maintaining an active lifestyle, achieving distance goals, and more.

An Antivirus Firm Believes That These Apps Might Lead To Scams

According to Dr. Web Antivirus, users may be required to watch a lot of adverts before receiving their prizes, or they may only be partially redeemable.

The antivirus company notes that there are three examples for these types of apps, which are Lucky Step Walking Tracker, WalkingJoy, and Lucky Habit: Health Tracker.

These apps have amassed a total of 20 million downloads between themselves, making them three of the apps still available on Google Play that promise sketchy rewards.

It is important to note that the fact that all three applications communicate with the same remote server address reveals a shared operator or developer.

The antivirus company claims that users cannot withdraw money from the apps until they have racked a substantial sum of awards, Bleeping Computer writes.

Even then, they guarantee that customers will unlock revenue after watching a dozen ad videos, and watching a round of ads push more ads to "speed up" the withdrawal process.

Along with these indicators, an earlier version of Lucky Step - Walking Tracker gave users the option to turn in-app rewards into gift cards that could be used to buy things from real online businesses.

However, this feature has been removed from the settings in more current iterations of the app, making it unclear what the prizes can now be converted to.

According to reviews submitted by customers, Lucky Step - Waling Tracker behaves like adware, loading full-screen ads upon screen unlocking and even replacing open windows.

Wonder Time, a rewards app with 500,000 downloads, is another illustration of a comparable product that is still accessible on Google Play.

The program makes the claim that users will receive real money for doing various tasks like downloading and installing extra software and games.

The tokens users earn for each action, however, pale in comparison to the developer's minimal earnings withdrawal barrier.

Read More: Adware on Google Play and Apple Store Gathers 13 Million Installs 

These Malicious Games Observe The Possibility Of Phishing Activities

Dr. Web Antivirus reported that there were over 450,000 downloads of phishing apps on Google Play that were passed off as investment apps and games in the same report.

It is important to note that the apps launch by connecting to a remote server, where they receive a configuration that tells them what to do.

The instructions typically involve opening phishing pages that ask visitors to provide sensitive information, putting users at risk.

Here are some of the malicious apps discovered by the antivirus firm:

• Golden Hunt - 100,000 downloads

• Reflector - 100,000 downloads

• Seven Golden Wolf blackjack - 100,000 downloads

• Unlimited Score - 50,000 downloads

• Big Decisions - 50,000 downloads

• Jewel Sea - 10,000 downloads

• Lux Fruits Game - 10,000 downloads

• Lucky Clover - 10,000 downloads

• King Blitz - 5,000 downloads

• Lucky Hammer - 1,000 downloads

Google has been contacted by Bleeping Computer to inquire about the security of the programs that are still available on the Play Store, but the company has not yet given a response.

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