A Survey Project for Android and Windows

I am looking for a freelancer who can create a market research survey for Android and Windows using multiple-choice questions. The survey is intended to gather data for an audit. The ideal candidate should have experience with Android app development and Windows too. I need a basic database (PostgreSQL) application that can be used on Android and Windows clients. For this reason, Xamarin or Flutter will be perfect to reduce development efforts. The purpose of the application is survey management for audits. I require the application to have multi-user access so that my team can all access and update the inventory data. In terms of features, I would like the application to have the ability to take photographs and avoid users to pass questions without answers. As for data storage, I would prefer free internet storage like Dropbox, Google Drive, etc... so that the data can be accessed from anywhere and is always up to date. The Windows application creates surveys and assigns surveys to specific users. Export surveys in Excel and Word format in the desired design. Design can be changed by the Windows user. No paid libraries allowed. Ideal skills and experience for this job would include: - Experience developing database applications for both Android and Windows platforms - Programming languages C# or Dart