If anyone has led you to believe that E2E means one specific device to another specific device at all times, they don't know what they're talking about. There

If anyone has led you to believe that E2E means one specific device to another specific device at all times, they don't know what they're talking about. There are different ways keys can be exchanged between devices (of the same user). All of them are E2E and secure. WhatsApp forces you to keep the phone around because the phone is the conduit for all communication even when you use it on the desktop. Signal has a desktop client that you need to link once to your phone, and works as a standalone client even when your phone is not around. Wire has E2E by default (like WhatsApp and Signal) and message synchronization across devices and platforms.