Laravel 5.2应用程序 - 自动同步两个mysql数据库

I have created web application using laravel, now I need to add functionality for users that when there is no internet connection available data must be stored in their local database, and when the system get internet connection than the data should be sync with the live sever. If we have only one client and one sever than I can use master-salve deployment, but here in my case there are more than 1 local clients. I have created web application using laravel, n