MakeKontakt is a switch for smart lights, where you swipe up/down to turn lights on or off and left/right to select a different light to control. Up to five individual lights or light groups are supported. Gestures are confirmed by animations on a ring of RGB LEDs for a natural user experience. MakeKontakt connects locally over wifi straight to your smart light system and has been primarily developed for the Philips Hue. However it can talk other protocols as well: LiFx, Yeelight and WiZ.
A single button on the back is used for connecting the device to your wifi network.
MakeKontakt is also an Arduino-compatible development platform based on the ESP8266. Apart from the wifi module it features the Broadcom APDS-9960 gesture sensor, WS2812 addressable LEDs and a CH340 USB to UART bridge all packed on a ~5cm diameter round PCB. You can use it for a remote status display for your CPU usage, an IFTTT trigger or even make a simple gesture game out of it.
The gesture sensor and the driver I'm using for it take some time getting used to. Also with small changes to the Arduino driver for the sensor I could not only decode up/down/left/right swipes but also swipes at odd angles. I made a small game that works as a training mode for MakeKontakt, where red ships appear and you need to shoot them by swiping in their direction. Hits are confirmed with a green plus while misses are indicated by a red X.
Placement of the ESP8266 on the original PCB was not really thought out. I did remove the copper pour from under the antenna but WiFi signal strenght was not great. Another problem was having just one hole for mounting the PCB in the case, leaving some wiggle to the assembly. Yet another issue with the original boards was that I underestimated how big of a hole in the case was needed for the APDS-9960 gesture sensor to work reliably with the drivers I found. Increasing the opening exposed some of the components around the sensor, so I needed to clear that space out. I have a new PCB version that should address these issues, with a cutout for the WiFi antenna.