I have gotten a bigger 2.42″ OLED display from Aliexpress. I got the 16pin version instead of the 7 pin one.
This is the copy of the SSD1306 that Adafruit sells and the same library works with it. It supports 8bit, I2C and SPI. The only problem I had was with the wiring for I2C. As usual, Aliexpress sellers do not offer any documentation or help. I managed to find some schematics online.
The main concern was to find a good combination of price, power and availability. The market is filled with cheap with IoT chips and single board computers.
Raspberry Pi Zero W
The hardware for my product had to be affordable. For the CPU I originally started the prototyping using a Raspberry Pi zero W the Wi-Fi version. My first PCB was based on this board. I used 90-degree SMD dual pin headers to connect the raspberry pi to the PCB. I went with SMD pin headers so I could keep the other side of the PCB clean and flush for the LCD-s.
For the screen, I wanted a challenge. I wanted to use multiple small one coloured OLED displays. The displays I found online were from Aliexpress. And are inexpensive for what they offer.
I have purchased a rather cheap gyro L3G4200D sensor from eBay that can detect 3 axis rotation and deliver it through an I2C or SPI interface. I tried to use it to detect horizontal and vertical rotation in real-time. This turned out quite difficult as I could not visualize what the Gyro was outputting. I needed a visualization. I ended up using Blender to visualize the gyro that is connected to an Arduino Uno. With this combination, I got a real-time report that turned out pretty good and proved the sensor to be quite accurate at what it does.