Earlier quoted context omitted.
I don’t understand what difference you are seeing. On the desktop you would have a UI button as well, and likewise a key on the keyboard. The difference I’m referring to is that Ctrl+Enter is arguably acceptable on the desktop, but has no equivalent on touch keyboards on mobile. Regarding the UI button, the way many people chat they would consider it too much friction to have to tap a button above the keyboard for ev…
No one uses the UI button to send a message on the desktop though. Everyone just presses Return to send, which is the most common need, and then once in a while realise they need to enter a newline without sending, for which there isn't a button so they need to learn how. Mobile doesn't necessarily have this issue because it can show the send button and the newline button at the same time and they're equally accessib…
Regarding on mobile, I’m familiar with chat apps that require a UI button press to send, and consider it unnecessary friction. It’s a larger mental leap to have to leave the keyboard.