Android Bluetooth Oscilloscope.

It can be used on any mobile device with Android, Windows, Linux and Mac systems, using Bluetooth technology. This means that there are no any wired connections to your phone, tablet or PC, which can guarantee the safety of your mobile device or PC, plus allows portability.
AR-oscilloscope is small enough that allows you to embedded it inside of any mobile system. This opens up new measurement possibilities for anyone working in fields like robotics or drones - see video
AR-oscilloscope Java API is available, so you can build you own software and implement any data analysis, anything you need.
The oscilloscope is the most frequently used, most flexible device for electric measurements. It visualizes an electric potential over time function, producing much more information than other potential and current measurement methods. With an oscilloscope the following quantities can be either directly or indirectly measured: direct voltage, alternating voltage, direct current, alternating current, time, time delay, phase, phase difference, frequency to view live waveforms, make measurements.