Well I have this one. https://www.amazon.com/dp/B09MKDRY7T/ref=cm_sw_r_awdo_2B3CBK2JV1ECXC3DM6RK
It connects to my phone via Bluetooth.
I also got some calibration stuff to make sure the tester was accurate.
Those I got were:
Oakton AO-00653-18 Oakton Conductivity and TDS Standard, 1413 Μs; 500 mL https://www.amazon.com/dp/B01MS6HNT9/ref=cm_sw_r_awdo_5E8NETF7G44TD3YNPEFA
And
Bluelab CAREKITPH pH Probe Care Kit with Calibration Supplies, Storage Solution, and Brush, Used for Pen, Meter, Monitor, Controller and Tools for Hydroponic System and Indoor Plant Grow, Clear https://www.amazon.com/dp/B00KM14Y18/ref=cm_sw_r_awdo_EBAF466QCQYDP7SKF3DN