Does the light need a battery?

Yes. The illumination runs on a small button-cell battery inside the barrel. Most versions are sealed, so the light lasts as long as the cell does.

Will the stylus work on any touchscreen?

It works on capacitive touchscreens, which covers most phones and tablets. It will not work on active-stylus screens that need a powered pen, such as an Apple Pencil or S Pen slot.

Can I put my logo on it?

Yes. It is sold as a custom promotional pen, and the logo is printed on the barrel. Ask the seller for the print area and artwork requirements before ordering.

What kind of refill does it take?

It uses a standard twist ballpoint refill. Check the refill length and type with the seller before buying spares, since the barrel is not a common brand.

Is it good for everyday writing?

It writes like a standard ballpoint, and the ribbed grip helps on longer notes. The plastic body and added light module make it heavier and bulkier than a simple stick pen.