Using outdated versions of systems and applications can be dangerous for the users themselves, but there are situations when customers do not care about updating software on their devices. WhatsApp wants to solve this way through coercion. Application creators have informed that in case users will use too old versions of the systems they will have to update them to slightly newer ones. Otherwise their WhatsApp accounts will be deleted. This situation applies to both Android and the iOS dedicated application.
To use WhatsApp without problems, you need to update Android at least to version 4.0 Ice Cream Sandwitch or newer, and in the case of iOS the oldest allowed version of the system will be version 9. Users have received time until 1st of February 2020 to update systems on their phones. If updates are not completed by then, customers will lose access to their accounts. For customers using Windows Phone, access to the application will be withdrawn on December 31, 2019, regardless of which system version the user has on smartphone.