Combing App is an application used to survey information of grocery stores across Vietnam. The application allows users to participate in surveys to earn extra income with each successful survey.

Grocery store survey information will be dynamically assigned to each survey campaign, so the survey questions and shooting criteria in the app will be different for users of different campaigns.

The application needs to get the user's current location while running in the background to draw the path taken by the surveyor, to support the survey without missing shops, missing routes and not overlapping. when looking at the map drew the lines the surveyor walked.