In the past few years, we have covered plenty of fancy coffee makers here. The DiFluid R2 Extract Coffee TDS Refractometer is another gadget that helps you make better coffee. It helps you find extraction levels and caffeine concentration in your drink.
This app connected gadget has a TDS range of 0 to 30% with 0.01% resolution. It has 3 testing modes (standard, multi & auto test). The device has rubber feet to stay put. It is tiny enough to fit in your pocket and has an aluminum sample dish. You can charge it via USB-C.