Meet the HALO: a smart pH probe that helps you measure pH in the field, lab, or anywhere else for that matter. The device has a companion iPad app that turns your tablet into a pH meter, allowing you to handle calibration, data logging, graphing, and data sharing. The HALO is a double junction, refillable glass pH probe with a built-in temperature sensor that connects to its app at the press of a button. It has a wireless range of 10 meters.
The HALO has a LED light that indicates when the device is active. Its CR2032 battery is easily replaceable. The companion app provides you with real-time pH and temperature data. It lets you log data and provides you with useful graphs. You can get this smart pH probe for $195 at this time.[Source]