Anti virus. Do I need it?

Being a current student in the IT field, I would say yes. Last school year a person who formally worked for the FBI as a network security head came to my school and gave a speech on mobile protection. What he said is you should definitely have an anti-virus on your android phone as mobile malware is a growing "field." He also said despite what people think, iPhones are NOT immune from malware. When my IT instructor did a mobile device unit, he said you should have several things "enabled" for the most security on your mobile device. A strong password, a backup program, an anti-theft/lost phone program, and for Android, an anti-virus. You do not have to BUY anti-virus/backup programs/anti-theft/ whatever for your phone. I use CM Security, ranked high by AV-Test.org. It is free, it not only scans for viruses, it also enables fixes for OS vulnerabilities. Cheetah Mobile, who makes CM Security has several other security apps. Including a free safe web browse, which protects you from online threats. In a nutshell the modern IT world recommends that you DO use anti-virus. But again, you do NOT have to pay for good mobile security.
 
There are many apps in play store which are virus or spy virus, if you don't have the right Anti Virus app your information will be send to hacker.. Anti Virus app is must for all the devices, no matter what.
 
I would say yes because apps on Play Store can slip through with some adware, spyware, virus etc.