Carpet cup holder, tray or side table?
Choose the solution around support and reach. Each solves a different part of floor-level drink placement.

Freestanding drink stabilizer
Steadi travels with compatible drinkware and widens its footprint without installation. It needs the entire 5.2-inch base supported on a firm, level spot. It can suit a clear floor-level position, but cannot make deep or uneven pile stable.
Rigid tray
A suitable tray can group items and provide a defined surface. Check the tray itself: it must not tilt, flex or rock on the rug. A rim does not establish liquid containment, and a tray can take up more floor space where people move.
Stable side table
A table raises the drink off the rug and can be positioned beside a floor-seated person. Choose a usable height and stable legs, with room to lift the drink comfortably. If the table rocks on the carpet, resolve that before setting down a drink.
Coaster or lidded drinkware
A coaster addresses surface contact according to its material and design; it is not automatically a stabilizer. A lid addresses the opening according to the drinkware’s design. Neither removes the need for support and sensible placement.
Make the decision in this order
First find firm, level support. Next check reach and traffic. Then check your drink’s fit and how much room the solution needs. If a separate table gives you a better spot, choose it. You do not need Steadi to justify choosing the more useful setup.