Nokia 8110 4G is running KaiOS, a successor of canceled Firefox OS. The same os is running on JioReliance phones, and maybe the most interesting thing about that is the Whatsapp support that phones have. KaiOS together with HMD announced that Whatsapp will be available for 8110 4G also back in the summer of 2018, but that still didn’t happen. When asked by a user of 8110 4G about the support for Whatsapp, KaiOS responded that Whatsapp is coming for that phone outside of India, but the exact date is still not known.
This should mean that in India you can install Whatsapp on your Nokia 8110 4G working on JioReliance network, but that still isn’t possible to do. It seems to me that owners of 8110 4G will be able to use Whatsapp when KaiOS sets up the app for the global release.
KaiOS should benefit greatly from the global support for Whatsapp and so will the sales of Nokia 8110 4G. But, until then the owners of the banana phone will have to wait a bit more for the popular communication app.