I disagree. These days smartphones can do almost everything that one can do on computer.
You can't really code on an mobile device.
You can't run a node on a mobile device.
You can't download software completely freely on a mobile device (technically you can, but most people can't).
Android is better hardened against potential attackers than Windows computers.
I 'd say, for the most part, if you have an android device and you are serious about security, you are good.