Various modular programs are written in cross C and C++ compiler for the functioning of ATMEGA 328-based handheld water quality measurement system. The main software module initializes the water quality sensors, analog to digital converter, E2 PROM, Bluetooth module, serial port and also checks all sensors connections along with battery level. A menu-driven program has been developed to operate smartphone-based water quality measurement system. Menu-driven program consists of testing and calibration submodules for testing of water samples and calibration of sensors, respectively. Calibration mode provides facility to calibrate device with standard buffer samples using 2, 3 and 5 point calibration algorithm. The smartphone-based application provides facility to select the sensor type and calibration method and further uploads the calculated calibration coefficients (offset and gain value) of linear models to the device. Device saves calibration coefficients in E2 PROM as a backup and also updates its prediction models with new calibration coefficients. Measurement mode consists of various submodules for data acquisition, storage, water quality parameters prediction and data transfer to the smartphone. Predicted parameters converted in to a single data chunk along with start, stop and a parity bit for transferring data to the smartphone without any error. It also includes I 2 C-based E2 PROM read and write module to recall the stored calibration coefficients. All modular programs have been linked to the main menu program to operate smartphone-based water quality measurement system.

Please Ref: S.Srivastava 2018, Smart phone based system for water quality analysis, Springer Link.

Detection and Spatial Mapping of Mercury Contamination in Water Samples Using a Smart-Phone

• Qingshan Wei†‡§Richie Nagi∥ Kayvon Sadeghi†‡Steve Feng† Eddie Yan† So Jung Ki⊥ Romain Caire† Derek Tseng† Aydogan Ozcan†‡§*

ACS Nano 2014821121-1129 Publication Date:January 20, 2014

Detection of environmental contamination such as trace-level toxic heavy metal ions mostly relies on bulky and costly analytical instruments. However, a considerable global need exists for portable, rapid, specific, sensitive, and cost-effective detection techniques that can be used in resource-limited and field settings. Here we introduce a smart-phone-based hand-held platform that allows the quantification of mercury(II) ions in water samples with parts per billion (ppb) level of sensitivity. For this task, we created an integrated opto-mechanical attachment to the built-in camera module of a smart-phone to digitally quantify mercury concentration using a plasmonic gold nanoparticle (Au NP) and aptamer based colorimetric transmission assay that is implemented in disposable test tubes. With this smart-phone attachment that weighs

Thanks a lot to everyone for your answers. I especially want to know about the popular Android-based apps that can be a good option for measuring and tracking water quality parameters. So far I have known Akvo Caddisfly is a good choice in this regard. Do anyone has worked with this app? Are there any other alternative open-source apps? what kind of instruments (probe, kits, sensor, photometer, etc) do I need for the testing of water quality and what should be the estimated cost?