I still use WhatsApp on my BB Classic daily. The native app died years ago so it's an emulated Android version, and for a long time I was capped at whichever the last version that supported Android 4.3 was. Mid-2020 I started getting notifications saying I would have to update the app at the end of the month or it would stop working, so I thought my luck had finally run out, but when the day came it gave me the option of updating the app, which somehow worked.
Has my WhatsApp always been connected and I never realized this is a requirement? That’s such an awful requirement. Or is it something like having to connect once a week? Either way I see how it doesn’t work if your only mobile device is a blackberry
Right now I am tolerating a extremely low ram KaiOS phone that often crashes... but I still prefer it to Android.