It's the end of an era - Nokia Series 40 phones have sent their last messages on WhatsApp as support for the platform expired on December 31. That comes after the Symbian S60 app stopped working in mid-2017. To be clear, this change affects only older Nokia feature phones. The current crop of Nokia-branded feature phones run on a mix of different platforms. Some are Series 30 (or 30+), others run Kai OS (8110 4G), Yun OS (3310 4G) or "other" (the 3310 3G software is just listed as "Smart Feature OS"). WhatsApp for Kai OS devices like the JioPhones (and presumable the Nokia 8110 4G) will...
Source: https://www.gsmarena.com/whatsapp_support_for_nokia_s40_phones_ended-news-34884.php