Android Question is it possible to create a chat app similar to WhatsApp without a central server?

[achtrade]

Just don't want the headache to maintain a server 24/7

 

[Erel]

You can send messages between devices connected to the same network.
[B4X] [B4XPages] Network + AsyncStreams + B4XSerializator

Building a "real" chat solution which works over the internet and works reliably will require a server.