YINMIK 4+

I purchased this tester for reading my PH levels for my 40 Gal and 75 Gal fish tank. It works good for reading PH levels but as far as Bluetooth connectivity it’s trash. You can go to settings on your phone to select it and it will connect that way until you go back to the app to see if it’s connected.
It does not connect to the app period so you are better off purchasing the model that’s no Bluetooth

Not certain what the other poor reviews are talking about. The app is unremarkable, but the BT connects properly and records the data as indicated. The application functions are extremely minimalist to be sure but the app is designed to read and record data whilst the probe is inserted in the ground. It records date, time, temperature, and pH. It is a bit annoying that the “save reading” button doesn’t actually save the data, you have to press the “disk” icon in the top right corner to actually save the data point.

The instructions that come with the probe are not exactly well written (which instructions are these days?), but one can probably figure it out without too much effort.

The device itself seems very fragile so users need to be careful handling the probe end especially when inserting it into soil with the metal protection “spear head”. And like the instructions indicate “NEVER unscrew the metal tip BEFORE removing any packed in soil or you will break the glass tip.

Was able to connect, see the result on phone, but it doesn't stay connected. Will have to power off then power on to connect and see history result. Not what is expected for app, waste of time. Anyone know what device will work?