The new App TieSight uses the camera of your Mac, iPhone or iPad to help you tie a tie. It costs US$3.99 for the Mac (10.7 or higher) and is available at the Mac App Store. The iOS version is free at the Apple App Store.
TieSight uses the front-facing camera of your device to help you tie a tie. The app shows you how to tie the perfect knot using an image of yourself on your device. All you have to do is to bring yourself into the right position and follow the instructions which TieSight will give you.
Additional tying instructions for seven further knots can be purchased from within the app for $1.99.