The reMarkable uses a battery less active stylus. A replacement can be bought in the official shop.
The following table contains a list of styli that have been tested with the reMarkable. Remember that the qualities of each stylus are subjective: test them before you buy them.
—- struct table —- schema: stylus cols: %title%, pressure, angle, calibration csv: 0 order: %title%
An in depth review video of various pens can be found here: "The Best Pen And Nib Combination For Remarkable (...)" at youtube, uploaded December 05, 2020
The following list contains the styli that are known to be not compatible with the reMarkable.
In general: styli that need batteries will not work and styli that are advertised as “compatible with any iOS or Android tablet” won't either.