Android Application for Data Collection

We are looking for an expert android developer, who can develop for us an android based data collection application. The application is to be used by field agents to collect data, and feed it into our system through an android application. The application should have the capacity to store data locally in case of remote areas with no internet, and then sync the data to the online database when internet connection is available. Meaning field agent is able to collect data with or without internet. The application should be built in java, android studio, and backend should be in PHP, Laravel framework. The developer should be an expert, providing clean code, and should also be able to use github, such that he can collaborate with our in-house engineers on certain sections of the app. Work should start straight away, and documentation is in the UI design, because UI is already developed, and XML files available; so the UI will enable you understand the flow of the app, because there is no written documentation. Only bid if you are able to start work immediately, and our budget is strictly $200, the app should be done in maximum two weeks (14 days), because its not a complex app, its simply data entry. We shall have two milestones, first of $100, released on finishing 50% of the work; and then the remaining $100 released on completing the project. Thank you