It seems that starting with the Galaxy Tab S3 (February/March 2017), Samsung has shifted to Apple's model: Sell tablets without a pen. Sell the pen as an optional attachment.
But something in the Note series (phones and tablets) used to be from Wacom. What is it, and is it still in the S3? And how does one navigate the future line-up? Does determining whether the words "capacitative display" appear in the tech specs settle it?
The Tab S3 has no dedicated slot for storing the S-Pen (unlike previous tabs equipped with the same tech) and the S line is not aimed squarely at content creators, which could be why Samsung opted to not include one in the sales package.
All S-Pens are backed by Wacom tech - the battery-free pens and their precise tips are a signature of Wacom's EMR (Electromagnetic Resonance) technology. Meanwhile, most if not all modern phones have a capacitive touch screen. You have to explicitly look for "S-Pen" when you need a device with it.
As of now (Sep. 2017), most S-Pen-equipped Samsung tablets still start their model numbers with a common letter "P":
(x for variant, e.g. 0 for WiFi, 5 for international LTE)
Tab S3 is a rare exception but it's marketed heavily around its S-Pen so you'd still know it easily.
Samsung once had a "C-Pen" denotation for a pen used on pure capacitive screens, although that's long obsolete.
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