Maintaining support for older versions of Android means additional resources for developers, which don’t always have to be paid for. As a result, as new versions of Android progress, support for older versions is periodically removed. WhatsApp will make this readjustment on November 1, when support for Android 4.0.4 or earlier is removed.
The current version of WhatsApp on Google Play already has a minimum requirement of Android 4.1 Jelly Bean or higher, but the app continues to work and is still supported on Android 4.0.4. In a short time, support will end on exactly November 1, when WhatsApp for this version of Android will be left to its own devices.
WhatsApp for Jelly Bean at least
Google ended support for Google Play services for Android Ice Cream Sandwich in 2020, although WhatsApp doesn’t really need these services to work. In other words, WhatsApp continues to run today on Android 4.0.4, a version of Android from 2012.
Precisely, Android 4.0.4 has been the minimum version required to use WhatsApp until this year, when the app slightly increased its minimum requirements on Android. Now the minimum you need is Android 4.1 to be able to use WhatsApp, as specified by the app on its FAQ page.
Not only that, but it is stated that from November 1, 2021, WhatsApp will no longer be compatible with Android 4.0.4 and earlier versions. This could be interpreted in two ways: that it does not work directly or that it is left on its own, so that it would continue to work until it shuts down.
Google hace ya mucho que dejó de informar sobre la distribución de Android, aunque los últimos datos oficiales -de hace ya más de un año- situaban a Ice Cream Sandwich por debajo del 0,2% del total, una cifra que debería ser todavía menor one year later. If you are still using WhatsApp in this version, it is recommended to upgrade to a mobile with a newer version or, at least, to export your chats.