About every 4-5 years unless something happens to my phone.

Whenever it keeps taking a dump w frequency. I don’t care too much as long as what I have is reliable.

I get a new phone when the old one passes away entirely. So it depends on how sturdy the current one is, or how careful I was not to wash it.

like. when it breaks

When a better model gets under £100 used.

i genuinely dgaf about having the latest phone, I'm not running out and paying 1000 bucks for an extra megapixel on the camera or whatever, it almost feels like a scam and so I keep my phone as long as it performs, I bought the latest Galaxy and I don't plan to replace it for years

..also every time an os upgrade gets available.