Mobile forms – Where to put the save and cancel buttons?

We are making a responsive website. There is a form on the site and I am not sure what type of save and cancel buttons to use where. I have found several patterns as you can see in the picture with the following variables: - Position of buttons (top/bottom, horizontal/vertical) - Autosave/Save button - Type of top buttons (text/icons)

Which solution is best practice?

Users usually fill out the form top to bottom (in this case) which would support buttons at the bottom, but convention might rather speak for the top buttons. Or do the top buttons rather belong to (native) app navigation and not to mobile site navigation? The battle for screen estate would speak for horizontal button positioning (cancel next to save), but supporting left handed people would speak for the vertical positioning. Maybe the cancel button can be even left out and the cross at the top or back button would cover this function sufficiently?