Using provided UI controls is consistent with how today's apps behave on mobile:

- For single-line text fields, pressing enter is an alias for submitting the form. - For multi-line text fields, pressing enter inserts a new line. There is no shortcut for submitting the form.

In mobile chat apps, the enter key inserts a new line, so you have to press the non-keyboard submit button to send a message. In mobile browser address bars, since they are single-line text fields, the enter key becomes a submit button on the virtual keyboard.