Long ago in the age of PDAs well before the era of smartphones, I bought a stylus that is built into a writing pen. It is the size of a typical writing pen and can be used as a stylus, mechanical pencil, black ink pen, or highlighter. It has a pocket clip, as do many good writing pens, so it stays in a shirt pocket. I long since forget the manufacturer or the location where I bought it, but I'm sure you can find a third-party stylus that fits your needs. Mine is fat like a writing pen which makes it easier for me to hold and use. My hands are too big to easily use the included skinny stylus.

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