This post is brought to you by RCS LT, maker of Combo Cleaner.
The vast majority of apps offering antivirus protection run on an open-source engine called Clam AV. It offers a convenient module that app developers can plug into their products for free and get passable antivirus protection.
Unfortunately, you often get what you pay for, which in this case is a subpar detection rate for malware and adware. That’s why a staff-maintained antivirus solution is a better idea.