Enable Unknown Sources: Go to Settings > Security and toggle on "Unknown Sources." This allows you to install apps from outside the Play Store.
Web Browser: In some cases, using a mobile browser to access web-based chat services is more stable than running a heavy app. Conclusion whatsapp apk for android 4.4.2
Feature Limitations: You will likely miss out on modern features like Communities, Polls, and advanced Privacy Settings. Enable Unknown Sources: Go to Settings > Security