 Hello everyone, today I would like to walk you through to the pocket science app. So this is the app which we developed in GSOC 2017. As you can see there is a home screen, there's this icon which displays device not found and device connected. So when the device is connected the icon would turn to green and the message displayed will be device found and it will show that it is connected and coming to the features of PSLab. So as you can see the main menu has been divided into five parts, home, applications, saved experiments, design experiments, settings. In the application menu we have further more options of oscilloscope, control, logical analyzer, data sensor, logger, sensor quick view and wave generator. In oscilloscope coming to the oscilloscope as you can see we have a four channel oscilloscope with three channels named CH1, CH2, CH3 and another for select for a mic. In the select mic option you can select the phone's own microphone as well as an external microphone connected to the PSLab board. So according to the channels which you wish to plot you can select the check boxes for those channels. There's an option for setting the range so the range can vary anywhere from between 500 millivolt to 16 volts and as you can see the graph here is much detailed with channel two channels plotted simultaneously and the time is also displayed. Coming to the other options there is time base for adjusting the time scale so it can be scaled from 875 microseconds to 102.4 milliseconds. Then we have the trigger function which helps in stabilizing the waveforms so we can select the channels to which we wish to apply the trigger and we can set the value of the trigger voltage. Then coming to the other features of the PSLab we have curve fitting techniques like sine fit and square fit and we can choose the channel for which we want to do that operation and we have the option for Fourier transforms. So the oscilloscope plots everything in the time domain but if we want to plot it in the frequency domain we can take the Fourier transform and finally coming to the xy plot. So in the xy plot the data of one channel is plotted with respect to another so we have two options for selecting the two channels that are required for xy plot and then you have to click on enable xy plot. So the relevant curve will be plotted. Now we are exiting the oscilloscope. Coming to the control part we have divided the control into three sections control read and advanced. So as you can see in the control part there are seven titles. So the first three of them correspond to voltage sources so they have been named PV1, PV2, PV3. The ranges of PV1 is from minus 5 to plus 5 volts PV2 is from minus 3.3 to plus 3.3 volts and PV3 is from 0 to 3.3 volts. So you can set the value manually as well as using these seek bars and also there are increment and decrement buttons provided here and once you have set the value just click on set and this will set the values and the value actually which has been implemented will be displayed in these boxes. Similarly we have PCS. PCS stands for current source. Its range is from 0 to 3.3 milliampere. Then we have wave 1 and wave 2. Wave 1 and wave 2 produce sinusoidal waves. The frequency the value entered here is the frequency of the waves which can vary from 5 to 5000 mega 5000 hertz and coming to the last option it's the square wave form so its frequency also varies from 5 to 5000 hertz and in this case the duty cycle by default is 0.5. Coming to the next section we have the read option. So here we have two push buttons and the value in the text boxes alongside it display the values of resistance and capacitance. Similarly we can also measure frequency and also count the pulses. For counting pulses and counting frequency we select the respective channels and then click on read and finally we have the reset button. So what the reset button does is all the values in these four options will be cleared. Similarly we have the facility to read the voltage as well. So as you can see voltage from six channels can be read. These six channels are marked on the PS lab board and as you click on read all the six values will be displayed. Coming to the advanced section. So at the advanced section has things like the waveform generator. So in this case for wave 1 and wave 2 you can select either sine or square waves and the frequency range is between 5 to 5000 hertz and you can also set the phase. The phase can vary between 0 to 180 degree. Similarly for PWM you can select which channel to use. Set the phase. Set the duty cycle. The duty cycle is between 0 to 1. Set the frequency and then click on set. Now if you want to use one of the pins as digital output you can select the respective checkboxes. So for square waves we have four channels sqr1234 and they can also be used for digital outputs. Then we have the logic analyzer. It's a four channel logic analyzer. So it can be used in single channel two channel three channel and four channel mode. So as you say as you click on that analyze button you will see the graphs displayed. So let me take to the four channel mode you can see four graphs will be displayed. Then coming on to the data sensor logger. So what the data sensor logger is it will if any sensor is any i2c sensor is connected to the ps lab board it will detect the sensor and it will provide an option to collect the data from the sensor. Similarly there are the sensor quick view and wave generator options. Sensor quick view has an auto scan button. So if a sensor is connected if you click on auto scan the hexadecimal address of that particular sensor and name of that sensor will be displayed. And then you can if multiple sensors are connected a list view of sensors will be displayed and let's select sensor and you can select the relevant sensor. Now coming to the saved experiments part the experiments have been categorized into electronics, electrical, physics, add-on and school level. So the electronics cover a large number of experiments like BJTs and feds, diodes, opamps, oscillators, communications. Similarly for the rest of them. So in total we have around 70 odd experiments already built in in ps lab. So as I click on input output characteristics each experiment has an experiment dock and an experiment set. As you can see the experiment dock shows what should be the connections and what should be the result obtained. As you can see we have provided screenshot of what should be the probable result and also there's a circuit diagram. And coming to the experiment setup part each experiment can be configured from the options like for this specific experiment we need initial voltage, final voltage, step size, gate voltage. For other experiments the requirements would be different and once these things are configured a graph will be plotted here. So the design experiment section is not yet done which we'll be doing soon and in the settings part we have an auto start option. So whenever the OTG is connected Android will prompt to open the ps lab app and then we have export data format. As I mentioned in the data sensor logger the data can be exported as TXT or CSV files. So we can set the file format from here. So this is the brief overview of the app. So the work on this app is still going on and we'd like if people come forward to contribute to it. Thank you.