WhatsApp for LG K4 (2017)

The K4 (2017) ships with Android 6.0/7.0, and modern WhatsApp is dropping support for very old builds, so first update via the Play Store and confirm you're on the latest version it will install. If it still crashes, clear the cache under Settings > Apps > WhatsApp > Storage > Clear Cache (not Clear Data, which deletes nothing from chats but resets settings), then reboot. If WhatsApp shows an unsupported-version message, back up your chats and move to a newer phone, since older OS versions are eventually cut off. See how others solved this on Reddit

For light messaging the K4 (2017) can still run WhatsApp and Telegram, but its 1GB RAM and Android 6/7 base make it slow and increasingly unsupported by app updates. To squeeze more life out of it, uninstall unused apps, disable bloatware via Settings > Apps, and keep only WhatsApp/Telegram plus a browser. If apps start refusing to update due to OS age, plan to migrate, because security and WhatsApp support for that Android version is ending. See how others solved this on Reddit

On the K4 open WhatsApp > Settings > Chats > Chat backup and tap Back Up to save to Google Drive using the same Google account you'll use on the new phone. On the new Android device, install WhatsApp, verify the same number, and when prompted choose Restore from Google Drive. If the K4's storage is full and the backup stalls, move photos to an SD card first so the backup can complete. See how others solved this on Reddit

The K4 (2017) only has about 8GB internal storage, which WhatsApp media fills quickly, so open WhatsApp > Settings > Storage and data > Manage storage to find and delete large videos and forwarded media. Insert a microSD card and set Camera and downloads to save there to free internal space. Also turn off auto-download under WhatsApp Settings > Storage and data so photos and videos don't pile up automatically. See how others solved this on Reddit

Yes, the K4 (2017) works well as a stripped-down phone for WhatsApp calls and texts. Disable or uninstall non-essential apps in Settings > Apps, turn off most notifications under Settings > Sound & notification, and keep WhatsApp's notifications on only for calls and direct chats. Mute noisy group chats inside WhatsApp by long-pressing the chat and choosing Mute to keep the device quiet and battery-friendly. See how others solved this on Reddit

Call quality on the K4 (2017) depends heavily on its modest hardware and connection, so confirm WhatsApp has microphone and phone permissions under Settings > Apps > WhatsApp > Permissions. For dropped calls, switch between Wi-Fi and mobile data since the K4's older radios handle weak signals poorly, and close background apps to free RAM before a call. If voice notes won't record, granting the microphone permission and restarting the phone usually resolves it. See how others solved this on Reddit