LaTeXiT is described as 'Small utility that allows you to quickly typeset LaTeX equations, without bothering with file creation, preambles, and so on. The PDF image obtained can then be exported by dragn drop to any application supporting it' and is an app in the education & reference category. There are more than 10 alternatives to LaTeXiT for a variety of platforms, including Windows, Mac, Web-based, Linux and iPad apps. The best LaTeXiT alternative is KLatexFormula, which is both free and Open Source. Other great apps like LaTeXiT are MathType, MathCapture, MathPad and Visual Math Editor.
Quick rendering of one-off mathematical formulas and easy export