A new dealer locator search tool has been added to the app.
"When a custom Mustang is created on the app or on the Web site, key aspects of the car — color, trim and engine choice — are input into a dealer inventory database, identifying dealers that have a similar Mustang in stock," Ford said in a statement.
The new feature gives buyers a "head start toward making that dream a reality by identifying a Mustang at a local dealership that is most similar to their creation," it added.
Ford rolled out the redesigned Mustang app late last week.
Prospective buyers have built more than 5.4 million custom Mustangs since 2012.
Edmunds says: An easy way to get your hands on your dream Mustang.