Does a form with continuous save need a "Save" button?

I am designing a web-app with a lot of forms and i was wondering how to improve the filling. The classical pattern is : fill, fill, fill, Save

Have you experimented a form which auto-save each field once you unfocused it ? In that case the Save button is no longer needed but maybe the user is reassured by it.

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Answer

As a user I don't like this idea at all.

There are 2 scenarios:

1. Creating an entity


2. Editing an entity

If I am in the create mode for say... a contact... as soon as I type "Dave" in a first name field it would have to create an entity... if I decide nah... I'm not going to add Dave after all, normally I just leave the screen and all is fine but in this case you're got a partial, and undesired entry in the system that the user didn't want.

If I am in the edit mode, I may start making some changes... then whoops wait... I entered the wrong data (or entered it in the wrong field)... no problem, just discard my changes and reload the form!... wait no, can't do that as it has overridden automatically.

The great thing about a Save button is that the user is giving explicit instructions to you to save the data up until that point the user expects that they haven't committed to anything.