Ken Van Hoeylandt's Tactility Is an OS for Your Espressif ESP32, Complete with Graphical Interface
Inspired by the Flipper Zero, Tactility includes the ability to configure your microcontroller, read the GPIO pins, and even load apps.
Software developer Ken Van Hoeylandt is working on a tool to boost the flexibility of display-equipped development boards built around Espressif's ESP32 family of microcontrollers: a custom operating system, complete with graphical user interface and loadable apps.
"It all started in December 2023, when I was considering to buy a Flipper Zero device," Van Hoeylandt explains, referring to the popular tinkerer's multitool. "Its software is very interesting and I found myself wondering whether I could port the code to another microcontroller (MCU). My porting efforts didn’t start out smoothly, but one thing led to another and 3 completely separate iterations later, I’ve got something that looks usable. The result is an application platform called Tactility."
Tactility's link back to the software on the Flipper Zero, a popular gadget originally sold as a "hacker's multitool," is its ability to run applications that aren't part of the core firmware — letting you load software onto a microSD Card, insert it into an Espressif ESP32-based device running Tactility, and run each application on-demand.
"There are about two dozen apps right now! That includes the various settings apps and some helpers like an alert, selection or input dialog app," Van Hoeylandt explains. "You might have guessed it, but the launcher in Tactility is just a 'special' kind of app! The Wi-Fi app is my favourite one. This was the hardest one to build, because of the complexity of Wi-Fi itself."
As well as the Wi-Fi app, which lets a Tactility device scan for and connect to nearby wireless networks, Van Hoyelandt has written apps that read the state of the microcontroller's general-purpose input/output (GPIO) pins and scan the I2C bus — "both apps can help a developer to debug issues with the hardware," the developer explains.
The Apple iOS-inspired graphical interface sits atop the FreeRTOS real-time operating system. "I guess it’s mostly a rebranding to call it an operating system instead of an application platform," Van Hoyelandt admits. "Considering that there's a launcher and apps, and you can develop applications with an SDK [Software Development Kit], and you can run apps from an SD Card… and the whole thing runs on FreeRTOS, I decided it is appropriate to call it an operating system."
More information on Tactility is available on the official website; Van Hoeylandt has written drivers for the LILYGO T-Deck and T-Deck Plus, M5Stack Core2 and CoreS3, and capacitive Cheap Yellow Display Board development boards. "Any ESP32 device with a touchscreen should be able to run Tactility," he notes, "because drivers can be implemented for any hardware."