There are some things that I couldnt understand about how whatsapp web can sync with IOS clients. Maybe someone may have a better approach than me. About the sync of ios app and web app of whatsapp . As you know IOS apps cannot run when they are on background or when they are suspended (if not specifically allowed by user and by apple of course and also whatsapp doesnt show the blue bar which background apps must show) so I'm eliminating that the app is working in background, however even if I kill my whatsapp in my Iphone , I still can use the whatsapp web. I only cant use it while my phone is off or in airplane mode. I dont know how it syncs the IOS client and web client.
First I thought there may be something like cloud databases for user's own google drive or icloud but I dont think whatsapp can handle that much of big data in cloud database. There should be something smarter than that Does anyone have any idea about that?