[michaelmrose]

Anything which supports multi-line input shouldn't submit on enter it should submit on button press so anyone can use it instantly without learning or remembering anything.

Then make it easier for users to learn that they can enter more quickly with control+enter which you can advertise via tooltip or adjacent text.

Better that 100% find it trivially usable even if only 75% learn they can do it faster

[layer8]

That isn’t workable for chat apps, at the very least on mobile. And that’s the most-used text entry interface that users nowadays grow up with. So I think you need to make an exception for such applications.

[debugnik]

Mobile makes this much easier actually, send can be a different button on the UI than the newline button on the touch keyboard without having to teach this to users. That's exactly how my phone is currently configured at least.

[layer8]

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 every send — more friction than Ctrl+Enter is on the desktop,

[debugnik]

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 accessible.

Regarding your edit:

> they would consider it too much friction to have to tap a button above the keyboard for every send

My finger travels almost the same distance from the home row to hit the send button above the upper right corner of the keyboard as the newline button on the lower right. I've been doing this for ages.

[layer8]

Actually, I do. Or at least I do in very similar situations where for some reason there is no keyboard shortcut to submit from the input field, so I press Tab (which moves the keyboard focus to the submit button next to the text field) and then press Return or Space to press the UI button.

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.

[debugnik]

> It’s a larger mental leap to have to leave the keyboard.

I find this interesting! I've never considered myself "leaving the keyboard" on the phone as if I were task switching. When I'm done typing I flow directly to the send button and let the keyboard go. The fact that the button is above the keyboard makes no difference to me as long as it stays accessible.

[oneeyedpigeon]

> so I press Tab

Now you have a bonus problem: how do you insert a Tab in a multi-line text box?