Underwater camera housing rarely leak, but if this event occurs the results are normally catastrophic causing irreparable damage to the camera body and lens.
SparkFun published a water detector project in 2013, where the original design was intended as a replacement for a NautiCam leak sensor. This project adapts the SparkFun design to an AdaFruit Trinket. The resulting implementation is sufficiently small as to fit within an Olympus PT-EP14 housing (e.g. for the Olympus OM-D E-M1 Mark II body).
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.