SimpleCV is described as 'Python interface to several powerful open source computer vision libraries in a single convenient package. With it, your software can have access to high level algorithms in feature detection, filtering, and pattern recognition in a unified framework' and is an app in the Development category. There are three alternatives to SimpleCV for a variety of platforms, including Android, Linux, Mac, Windows and Self-Hosted solutions. The best alternative is OpenCV, which is both free and Open Source. Other great apps like SimpleCV are BoofCV (Free, Open Source) and Simple Photo Gallery (Free).
BoofCV is an open source library written from scratch for real-time computer vision. Its functionality includes, low-level image processing, camera calibration, feature detection/tracking, structure-from-motion, fiducial detection, and recognition.
Simple Photo Gallery shows up your photos in an impressive and memorable way. This gallery extension easily organizes your large set of digital photos, edit images and create multiple albums. The images can be viewed in a full screen slide show view.