WhatsApp for OnePlus 6T

After the OxygenOS 11 (Android 11) update WhatsApp's media folder moved under Android/media/com.whatsapp, and an old WhatsApp folder in internal storage can linger as a duplicate, inflating the reported size. First open WhatsApp > Settings > Storage and data > Manage storage to find and delete the largest files and forwarded media per chat. Then in Android Settings > Apps > WhatsApp > Storage usage, tap Clear cache (do not Clear data, that would wipe chats). Finally, use the OnePlus File Manager or Files by Google to check both Android/media/com.whatsapp/WhatsApp and any leftover WhatsApp folder in internal storage, and remove the old duplicate copy. See how others solved this on Reddit

WhatsApp's built-in in-app camera uses a low-resolution, heavily compressed stream, so it looks far worse than the 6T's real camera. Instead of shooting inside WhatsApp, take the photo with the stock OnePlus Camera app first, then in a chat tap the attach (paperclip) icon > Gallery and pick it; if WhatsApp shows an HD toggle on the image, switch it to HD before sending. For maximum quality, attach the photo as a Document instead, which sends the original file with no recompression at all. See how others solved this on Reddit

On the OnePlus 6 and 6T, WhatsApp calls can grab the wrong audio path and downgrade quality, and the problem is worse over Bluetooth. First fully update WhatsApp from the Play Store, since many call-audio bugs were fixed in later builds. If a Bluetooth headset sounds muffled or robotic, disconnect it and test the call on the phone's own speaker or earpiece to confirm Bluetooth is the cause. Also go to Android Settings > Apps > WhatsApp > Permissions and confirm Microphone access is allowed, and close any third-party call-recording app, since those hook the call audio stream and can degrade it. See how others solved this on Reddit

First turn off bulk auto-download so your gallery isn't flooded: WhatsApp > Settings > Storage and data, then uncheck the media types under When using mobile data, When connected on Wi-Fi, and When roaming. To save a single item, open that photo or video full-screen in the chat and tap the three-dot menu in the top corner, then choose Share to send just that file to Google Photos, the OnePlus Gallery, or Files. Only media you have actually downloaded and opened gets written to storage, so saving one item this way won't pull in the rest of the chat. See how others solved this on Reddit

Most OnePlus WhatsApp glitches come from OxygenOS's aggressive battery optimization killing the app in the background. Go to Settings > Battery > Battery optimization, find WhatsApp and set it to Don't optimize, then under Settings > Apps > WhatsApp > Battery allow background activity. Next clear the app cache via Settings > Apps > WhatsApp > Storage usage > Clear cache (not Clear data), and update WhatsApp from the Play Store, since outdated builds are a common cause of crashes right after a system update. See how others solved this on Reddit