Do NOT update to One UI 4 on Samsung S21, if your carrier relies on VoLTE and wifi calling exclusively for phone calls, SMS(May affect other models too) : r/samsung
Sounds, vibrations, and notifications on your Galaxy phone or tablet
Galaxy S21/Ultra/Plus: How to Compose/Send a Text Message - YouTube
Chat features removed in latest version of Samsung messages? - Samsung Community
4 Easy ways to Transfer Text Messages from Samsung to Computer
Change the default messaging app on your Galaxy phone
Samsung makes Google Messages as default SMS app for Galaxy S22 series - The Economic Times
Synchronize Samsung Galaxy S21 FE 5G sm-g990e - PhoneCopy
Set up your Samsung Galaxy S21 Ultra 5G Android 11.0 for text messaging -
Set up SMS - Samsung Galaxy S21 5G - Android 13 - Device Guides
How To Fix It If Your Samsung Galaxy S21 Can't Receive Text Messages
Galaxy S21/Ultra/Plus: How to Set the Default SMS App - YouTube
Galaxy S21/Ultra/Plus: How to Enable/Disable Get SMS Delivery Reports - YouTube
How can I increase data entry area in Samsung Messages SMS? | Android Forums