How dodgy is it without security updates? There are mixed views online. I'm using a note 10. Brilliant phone. I love its size and weight - not like carrying round a tablet! And I have been using a stylus for 30 years - since the days of the Palm5. Can't do without it. Some say "get a new phone". However manufacturer updates are sometimes only for about 3 years for a new phone. So then I would be back where I started. I resent paying a grand for a new phone, when this old beast does all I want it to. Others say "don't be paranoid. You won't get hacked!" The other option is a custom ROM. But some of them have no security updates either!
I have Norton on it, and avoid dodgy apps & websites. So am I paranoid?