It’s bad enough that computers can have spyware and viruses. But your phone too is also a 
possibility – and to my thinking, a much more desirable target. Do you have a banking app on your phone? Do you check your stocks or retirement accounts on it?
“A Lookout threat report this year said a tiny but growing portion of its Android user base in the United States – half a percentage point – had unwittingly downloaded mobile Trojans. And 1.6 percent have downloaded adware that pilfers their personal data without their knowledge.” (Click here for the complete article on the NY Times.)With Android in particular being so susceptible, I highly recommend that either you do nothing that could be compromised on it, or have security software on it.