i-Sleep is an innovation developed from the concept of analyzing expired breath during sleep for screening and monitoring sleep apnea conditions. i-Sleep continuously assesses respiratory functions with minimal patient effort in various sleep settings. The screening and monitoring tool for sleep apnea is made up as a lightweight and portable tool to deliver mobility and convenience to user. Screening of sleep apnea using expired breath during sleep analysis enables non-invasive sampling technique, which eliminates high resource settings. i-Sleep comes with a screen displaying the novel sleep apnea index, end tidal cardon dioxide (EtCO2) and respiration rate (RR). The patients only need to breathe comfortably during sleep to get the results. i-Sleep comes with a standard USB/SD card data storage powered by rechargeable batteries allowing data to be saved, monitored, and analyzed. The device can connect to smartphones via mobile apps where patients can independently monitor as well as manage their conditions. i-Sleep offers 16GB worth of storage for data recording and saving. i-Sleep's data can be accessed through a computer via a USB connection. With the data (in.csv format), users are free to replot, print etc. Assembled with quality components that are cost-efficient, i-Sleep delivers smooth real-time waveform that improve diagnosis and enhance its reliability.