What is GPIO Flipper Zero?
You can use your Flipper Zero for hardware exploration, firmware flashing, debugging, and fuzzing. Flipper Zero can be connected to hardware using its built-in GPIO pins, control hardware with buttons, run your code, and show debug messages on the LCD screen. Flipper Zero can also be used as a USB to UART/SPI/I2C converter.
Flipper Zero Documentation
Links
Flipper Zero’s GPIO pins

Flipper Zero has 18 pins on the top side, consisting of power supply pins and I/O pins. Power supply pins can be used to power your external modules. Input/output (I/O) pins are +3.3 V tolerant for input and output, some pins are +5 V tolerant for input only – keep it in mind. I/O pins connect external modules to the I/O pins of the STM32WB55 microcontroller through 51 Ohm resistors. All pins are electrostatic discharge (ESD) protected. For information on the basic functionality of Flipper Zero pins, see the picture below.
Flipper Zero GPIO documentation
Utilities of the GPIO on a Flipper Zero
Flipper zero gpio wifi Module

The Flipper Zero Wi-Fi Module is both a debugger and a programmer for Flipper Zero. It replaces the ST-Link debugger. It is based on the ESP32-S2 module and the open-source firmware project Black Magic Probe. It can flash and debug various microprocessors and microcontrollers (including the one used in the Flipper Zero) via Wi-Fi or USB. This module can also act as a USB-UART adapter.
Other modules you can find on the internet

This is a fully built and flashed esp32 cam board for the flipper zero on a custom circuit board. Board runs Mayhem code from from Eried which is a fork from Here for marauder and Flipper-Zero Camera for the camera. This board has the internal antenna on the PCB. No external antenna options at this time. The boards components are in stock but made to order. Usually this can be done in 2-3 days.
Find more flipper zero accessories here
Is a Flipper Zero illegal?
No, the Flipper Zero is a legal hacking tool. However, using this tool may be illegal. It is your actions that may be illegal, not the tool itself.
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