All these people saying Android is based on Linux and thus virus/malware cannot infect it are so wrong. I have seen so many malware infecting Android phones in which the malware get root access in the background, making itself a system file and automatically downloading more malware/adware. As the malware turn itself into a system file, you cannot get rid of it using a restore/wipe/reset. Only flashing the phone will get rid of it.

But, as many already mentioned, you will get infected only from installing compromised apps, in which you have to interact and give permission yourself. It cannot silently install by itself. surfing shady sites like porn sites can infect you, but it will still require user interaction.

So my answer is if you are careful and not turning on unknown source, you won't probably get infected. but having antivirus won't hurt much as it will detect malware even before it gets installed.