Quick summary: Adafruit has launched the $34.95 Metro ESP32-P4AliExpress price Hydra, an Arduino UNO-shaped development board that combines an ESP32-P4AliExpress price application processor with a separate ESP32-C6AliExpress price wireless coprocessor. It adds 16 MB each of flash and PSRAM, two-lane MIPI display and camera connectors, USB High-Speed host, microSD and familiar shield-style headers. The catch is equally important: this first board uses ESP32-P4 v1 silicon, its GPIO is 3.3 V, and some software paths are still early.
Two ESP32 chips with different jobs
Adafruit announced the Metro ESP32-P4 Hydra on 26 October 2026 and listed it for sale rather than pre-order. The board’s main processor is an ESP32-P4 v1, with two 32-bit RISC-V cores running at up to 360 MHz and a separate 40 MHz low-power core. Adafruit pairs it with 16 MB of QSPI NOR flash and 16 MB of PSRAM.
The P4 is the application processor, but it does not contain a radio. Wireless networking comes from a second chip: an ESP32-C6 connected over SDIO. Adafruit describes Wi-Fi 6 as the board’s ready high-speed wireless path. Although the C6 silicon also supports Bluetooth LE 5.3, Thread and Zigbee, the company warns that additional interfacing firmware may be needed to expose those protocols. A C6 on the PCB therefore does not make every radio mode immediately available to an application.
| Feature | Metro ESP32-P4 Hydra |
|---|---|
| Main processor | ESP32-P4 v1, dual-core RISC-V up to 360 MHz |
| Wireless coprocessor | ESP32-C6 over SDIO; 2.4 GHz Wi-Fi 6 |
| Memory | 16 MB QSPI flash and 16 MB PSRAM |
| Display and camera | Separate 22-pin, two-lane MIPI DSI and CSI connectors |
| Storage and USB | Four-bit microSD, USB-C device/debug and USB-A High-Speed host |
| Expansion | UNO/Metro-style headers, separate SPI header and STEMMA QT; 3.3 V logic |
| Power | USB-C, 7–12 V barrel input or one-cell LiPo with charging |
Built for displays, cameras and USB peripherals
The most interesting additions are the P4’s multimedia interfaces. The Hydra exposes separate two-lane MIPI DSI and CSI connectors in the 22-pin Raspberry Pi format. Adafruit lists the 5-inch and 7-inch Raspberry Pi Touch Display 2 and OV5647-based “Zero” cameras as compatible examples. It explicitly says the newer IMX708 Camera Module 3 is not supported.
A USB-A port provides 480 Mbit/s USB 2.0 High-Speed host capability, including a controllable 5 V boost supply for battery-powered projects. The main USB-C port handles power, programming, serial debugging and TinyUF2 updates. A four-bit SDIO microSD slot rounds out the useful I/O for local media, logs and camera data.
That combination makes the board more credible for smart displays, camera appliances, control panels and USB-host projects than a conventional Wi-Fi sensor node. Our ESP32-P4 versus ESP32-S3 comparison explains why the P4 is the stronger multimedia part, while the ESP32-P4 Function-EV-Board guide shows what a fuller reference platform exposes.
Familiar shape, important limitations
The UNO-style footprint should make mechanical prototyping convenient, but it is not a promise of universal shield compatibility. Adafruit says all GPIO uses 3.3 V logic, so shields expecting 5 V signals need careful checking. The board also uses the original ESP32-P4 v1 chipset, not the newer ESP32-P4X v3; Adafruit tells buyers who specifically require P4X not to purchase this version.
Software maturity is another consideration. CircuitPython 11.0.0-alpha.2 lists the ESP32-P4 port as alpha, with bugs and missing functionality expected. Adafruit’s Arduino continuous-integration configuration also points the Metro P4 at a temporary source core until a formal board definition is released. Buyers should expect active development rather than the polished library coverage of a mature ESP32-S3 board, and there is no basis yet to assume ESPHome support simply because the hardware contains ESP32 chips.
Price and availability
Adafruit lists the Metro ESP32-P4 Hydra at $34.95 in the United States and, at the time of writing, as an in-stock product that can ship rather than a future pre-order. Distributor availability, tax and regional pricing will vary.