Read more: What it means when your phone isn't supported anymoreGoogle Play System Updates improves security even after manufacturer support ends, but it's not a complete alternative to security patches.
With that in mind, reaching the end of promised security updates is a good indicator that it’s time to look for a new smartphone. It doesn’t have to be immediately, but you’d be tempting fate by keeping sensitive information on a phone running security measures that are a year or more out of date.
When it’s time to upgrade, look for a brand that offers long-term support that’ll keep your new handset running securely for as long as possible.
How many are running end of life Android?
My vote: Android 10.