I’m thinking of upgrading from my iPhone 7, so I’m planning on having another phone for ~3-5 years. The Galaxy s9 looks like a neat price, but I’m wondering how long are android phones supported, security-wise? Apple supports their phones for life, so do different brands support their phones for different lengths of time? What might be the longest I can keep a phone after launch?
Android updates (new versions, Android 9, Android 10, etc..)... are supported for 2 years usually, but it depends on the manufacturer (till the warranty runs out).
Security updates for another 2 years maybe more.... again depends on the manufacturer.
If you want your device to be supported security wise, you should buy new model!
S9 is old model now, it will soon be left only with Security updates!
The Pixel phones (made by google) have the longest Android and Security life span.
If you're not worried about security and your talking about applications, it can last up to 6-7 years...