WhatsApp for Samsung Galaxy S10 Plus

WhatsApp downscales and recompresses photos by default to save data, which makes your S10 Plus camera shots look soft and washed out. In WhatsApp tap the three-dot menu, go to Settings > Storage and data > Media upload quality and set it to HD (Best quality), and when attaching a picture use the document (file) icon instead of the gallery icon to send it as an uncompressed original. For received media that looks bad, the only fix is asking the sender to enable HD or send it as a document too. See how others solved this on Reddit

WhatsApp video calls run the selfie camera at a low, heavily compressed resolution that has nothing to do with your S10 Plus hardware, and a weak Wi-Fi or mobile signal makes it worse. Make sure WhatsApp has Camera and Microphone permission under Settings > Apps > WhatsApp > Permissions, clean the front lens, and call over a strong 5GHz Wi-Fi connection for the best stream. Call quality is capped by WhatsApp's servers, so a stable, fast connection is the biggest factor you control. See how others solved this on Reddit

This usually happens when One UI's battery optimization or a clash with the regular phone-call audio channel suspends WhatsApp the moment a call connects. Go to Settings > Apps > WhatsApp > Battery and set it to Unrestricted, then under Settings > Apps > WhatsApp > Mobile data make sure Allow background data usage and Allow data usage while Data saver is on are both enabled. Also end any active normal phone call first, since the S10 Plus will park a WhatsApp call on hold if it thinks another call is using the audio. See how others solved this on Reddit

One UI's aggressive power management is the usual culprit, putting WhatsApp to sleep so messages only appear when you open the app. Go to Settings > Apps > WhatsApp > Battery and choose Unrestricted, then open Settings > Device care > Battery > Background usage limits and remove WhatsApp from both the Sleeping and Deep sleeping app lists. Finally confirm Settings > Apps > WhatsApp > Notifications is on and that Do not disturb isn't silencing it. See how others solved this on Reddit

When a single app loses data while everything else connects, it's almost always a stale cache, a restricted-data setting, or a VPN/private DNS quirk affecting just WhatsApp. Go to Settings > Apps > WhatsApp > Mobile data and enable Allow background data usage, then clear the cache via Settings > Apps > WhatsApp > Storage > Clear cache and restart the phone. If you use a VPN or have set a Private DNS under Settings > Connections > More connection settings, try turning it off, since those can selectively block WhatsApp's servers. See how others solved this on Reddit

Yes, your S10 Plus stays the main phone and you add the tablet through WhatsApp's linked-devices feature rather than a second install. On the S10 Plus open WhatsApp > three-dot menu > Linked devices > Link a device, then use it to scan the QR code shown by WhatsApp on the tablet (companion mode) or by WhatsApp Web. The tablet can then send and receive on the same number independently, even when your phone is offline for up to about two weeks. See how others solved this on Reddit