Python (Kivy or similar) cross-platform developer for an small web, iOs, Andoird, MacOsx,Windows app

It's a FIXED-PRICE project managed with upfront and milestones. The proposed budget is indicative. The project scope is to create a single tool - aimed at both the users and the administration users - to facilitate and standardize the process of creating internal documents currently managed with the help of Google Drive. The development of a application cross-form: web, iOs, Andoird, MacOSx, Windows, Linux exploiting the technology of the framework python using [login to view URL] (or similar) and completely integrating the current storage in Google Drive cloud without altering the 'current data storage in the cloud but improving usability even offline. The applications, will allow the users: - to log in using their Google account, - online and offline consultation of the patient list, - online and offline consultation of patient details (useful information) - online and offline consultation of all documents attached to a patient present in the patient's Google Folder - registering a video using the Camera of the device - saving the videos in Google Drive cloud (directly in the patient's own folder) - the creation online and offline DTNs (daily treatment notes) using the google forms currently existing but also in offline mode to prevent compilation errors due to the loss of the internet connection - the consultation of the google calendar - the creation of events in the own calendar - chat and messaging between users (users and administrators) - get push notification by the administrators - synchronize with the google drive the contents produced offline when the device has an internet connection The web application of the administration, would be located at a web address as a subdomain, also the web application will allow the administration to: - create/edit/delete a Google user to use the applications - create/edit/delete a patient in the application - associate a patient to a folder path in Google Drive - associate a patient to a specific form path in Google Drive - Send a push notification (text) to an user The freelance have to use our Sketch design, we would provide source file. The freelance have to choose the best cross-platform framework. The freelance have to define milestones. The freelance have to delivery the application source files but ALSO publish the apps in the iOs and google Play Marketplace of the client.