Civil Protection / Information Web app corversion to Native mobile

Hello, we are a new dev company and we curently have a web app written in JS, HTML, CSS, PHP. It is a civil protection / infromation app for municipalities. It also implements sms and notification services for the municipalities to be able to communicate directly with their citizens that download the application. In the application the civilian makes an account and uses the application to be informed about the news of the municipality, receive information about daily issues through notifications and also receive Emergency SMSs in case of a public emergency. We want all that information (News, SMSs, notifications) to be managed by an asigned admin in every municipality. So we also need an admin managment page through which the admin can create all that content. Another feature is the ability of the civilian to press an SOS button which will immediately send a notification to the municipality admin (or any other asigned user) with their geo location and their status. All municipalities should have their own content and users, so we want the user to be able to select their municipality when they open the app and be transfered to the content of that municipality. Plus some other interesting simple features. Currently we have a semi-final version that has some issues and some features missing. But we decided we need to make it into a native IOS/Android app. With our size it is impossible to make it in time. So we need to oursource the conversion of the application while we also need from the team that will convert it to address some bugs and implement some of the missing features. We would prefer if the app was written in React Native for the front-end and either use Firebase as a backEnd service or NodeJs with whichever DB you see fit.