ChatApp is the application for chatting. Using this app you can send a message to the person who is in your contact list and who is using this application. ChatApp will provide fast messaging service. ChatApp use firebase for messaging, firebase is the cloud messaging service. It will send and receive messages instantly. Firebase is a real-time database, it stores and sync data with NoSQL cloud service. Data is synced across all clients in real time, and remains available when your app goes offline.