Android has been the favorite of malicious code writers since August 2010, when the first Trojan program targeting the OS was detected.

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Once launched, the virus is designed to install a Trojan horse or backdoor program, and allow investigators to record everything typed into that machine, thereby getting around encryption and passwords.

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The ring allegedly used a "malware" program called "Zeus Trojan" to hijack accounts, embedding it in email messages and attachments.

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But no matter how good your antivirus program is, if you open a suspect email, you make yourself vulnerable to Trojan horses that steal email and bank-access information.

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