Push notification Web and Mobile App

I have a mobile app template called Universal which I bought on Codecanyon which I want to use for the project described below: Mobile App: (Android and IOS versions) The purpose of the app is to function as an emergency app that links to an existing MySQL database with close to 10k members. The best example app is Namola ([login to view URL]). The idea is to have the app send out push notifications to all members within 100km of the person in danger e.g. person A is in danger, he/she opens the app, hits the panic button and an emergency push notification is sent to all other members in the specified radius. The notification must, first of all, make a distinct sound upon receipt (it is for emergency situations), and secondly provide the recipients with sufficient info on the person in danger including live location, name and surname, contact number, family members and their home address, which is all kept in the database. The best way would probably be the persons live location, name and cell number and then the rest of the info like family members, etc. in the app upon clicking the notification. Here are some key features I need: 1. Login/Sign Up screen with the option to sign up as a single user or family. 2. Home Screen with Google Map of user's current location and a large panic button that changes to cancel emergency once pressed. Canceling will, of course, send out that the crises have been averted. 3. When in alert the app must continuously update the user's location to the server using displacement-based location updates to cater for e.g. a person in a car. 4. Profile page to view/edit details and manage family members as well. 5. Notifications page to show a list of all the push notifications received. 6. Settings Screen must have the option of switching the language between English and Afrikaans. Web App: (PHP and MySQL) The web app exists already but it needs to be integrated with the mobile app and OneSignal/FCM. The web app is used by admin staff to manage members and communicate important information to them so the goal here is to allow the admin staff to push notifications to their mobile app users either individually, per family, per region or to all members. The web app, of course, also uses the same database as the mobile app. To log into the concept web app on my development server and have a look you can visit [login to view URL] using username 3lancer and password 3lance. The site uses WP to handle logins but is build independent of WP using HTML, CSS, JS and the datatables editor JS plugin. Should you have any questions feel free to ask! Thanks!