This is arguably the "killer feature." You snap a photo on your phone, and within seconds, it appears in the "Photos" tab on your PC. No more emailing photos to yourself just to get them onto your desktop. You can drag and drop images directly from the phone app into Photoshop, Word documents, or emails.
You can adapt the details based on the specific app you are evaluating (e.g., Samsung Flow, KDE Connect, Dell Mobile Connect). your phone companion app
Send and receive SMS/MMS messages using your computer keyboard. This is arguably the "killer feature
No more searching for your phone when it vibrates. and within seconds