Even though adding wireless connectivity to a device is so easy, there are still plenty of devices on the market that show a painful lack of it. I recently got a digital picture frame as a gift, and it turned out that it can only show pictures from a SD card or USB drive attached to it. That means to add or change the pictures that are displayed, I have to remove the drive, attach it to my computer and copy over the pictures and then reattach the drive to the frame - just too much work! In fact, practically, I might want to put the frame on a shelf, and it might not even be easily accessible to update the pictures.

To get around the problem, I have designed an ESP32 board which can be plugged into the USB slot. It has an SD card slot to add memory, and the USB2244 bridge IC that makes the SD card appear as a USB Mass Storage device. The board is powered by USB, and software running on the ESP32 runs a server, allowing wireless access to the files on the SD card. Note that I use the NINA W102 module from UBlox, which has an ESP32 under the hood.

While this was designed to solve a very specific problem, you can imagine lots of scenarios where being able to quickly access a pendrive wirelessly would make life easier.