For Historical information it is probably best to type History:Dobb's Ferry into any search bar such as Google. That should bring you to several links that give you details on this region, including excerpts from books, articles and reference sources etc.
The example below indicates that the site was named after a local fisherman who provided ferry service across the Hudson to increase his income.
"Dobbs Ferry is a village within the town of Greenburgh and was part of Philipsburgh Manor.
"Dobbs Ferry is an incorporated village, commencing two miles north of the northerly line of the city of Yonkers, and five miles north of the northerly line of the city of New York, as now established. It is nearly square in form, and its boundary lines are a trifle in excess of a mile in length on each of its four sides...."
"The name of Dobbs Ferry is derived from the fact that one Jeremiah Dobbs, a Swede, who was a fisherman, and lived at Willow Point, near the southern line of the present village, added to his meagre income, prior to and during the Revolution, by ferrying occasional travelers across the Hudson."
[Source: Excerpts from Scharf's History of Westchester County,..., Volume 2, Chapter II, Greenburgh, pages 184-5; published in 1886.]"