The Raspberry Pi Foundation has refreshed the Pi Zero, its ultra-compact SBC. The Pi Zero 2 W retains the I/O of its predecessors, but with superior performance. The Pi Zero 2 W is available to order in numerous markets and costs US$15 in the US.
https://www.notebookcheck.net/Raspberry-Pi-Zero-2-W-launched-for-US-15-with-5x-the-performance-of-the-original-Pi-Zero.576677.0.html