The next aspect to the scam-like operation is that when the
user clicks on an advertisement to download the application,
the ad library launches a web page that looks very similar in
appearance to a native Android dialog box prompting the user
to download and install the antivirus application through the
“Download & Scan FREE Now” button. Upon clicking this
button, a file by the name of “Scan-For-Viruses-Now.apk” is
downloaded. We note that Tapcontext embeds a unique identifier
to each click so that the URL of the web page is different
every time while the appearance is the same. However, all the
URLs come from two domains only: www.fastermobile.org
and www.fastermobiles.com. Furthermore, each downloaded
Scan-For-Viruses-Now.apk file is the same application (has the
same functionality) but is slightly different so that their MD5
and SHA digests never match.