The soil pH Meter or sensor is a device that measures the current pH of the soil. It detects the pH value of the soil by inserting two stainless steel probes vertically into the soil.

Soil pH meters are devices used by home gardeners and agricultural professionals to measure the acidity or alkalinity of soil. Getting your soil pH right is a must if you want to produce healthy, vibrant plants. To get accurate measurements you need to know the right procedure for your soil pH meter.
The device is similar to the digital meter which also measures acidity and alkalinity in a different sphere

What to look for when selecting your soil pH meter

1. Portability. Will you need a pH meter that is lab-based, field-based or a combination?
2. Method. Can soil be sampled directly or is dilution required?
3. Functions. Are other built-in functions required? For example, soil moisture and conductivity.
4. Length of the probe. The minimum sample depth is generally 20cm. Different plants and crops require measurements to be taken at varying depths.
5. Accuracy. Traditionally direct soil sampling is less accurate than the dilution method.
6. Calibration. Does the device come with any buffer solutions to calibrate your meter?
7. Sampling time. How long does it take to get a result?
   More details can be found out about the Soil Ph meter here.