RedCrab Calculator is described as 'mathematics software with fullscreen editor for the free placement of algebraic formulas on the worksheet in mathematical notation' and is an app in the Education & Reference category. There are more than 10 alternatives to RedCrab Calculator for a variety of platforms, including Mac, Windows, Online / Web-based, Linux and iPad. The best alternative is Overleaf, which is both free and Open Source. Other great apps like RedCrab Calculator are LibreOffice - Math (Free, Open Source), MathType (Paid), KLatexFormula (Free, Open Source) and Typeset (Freemium).
Math is the LibreOffice suite's formula editor, that can be invoked in your text documents, spreadsheets, presentations and drawings, to enable you to insert perfectly-formatted mathematical and scientific formulas.
MathType is a powerful interactive equation editor for Windows and Macintosh that lets you create mathematical notation for word processing, web pages, desktop publishing, presentations, elearning, and for TeX, LaTeX, and MathML documents.
Getting your research published is tough. You face complex author guidelines, painful citation formatting, messy email collaboration, frustrating word templates, and long drawn submission processes. The good news? Typeset makes it easy.
Math, part of the Apache OpenOffice suite, is a tool for creating and editing mathematical equations, similar to Microsoft Equation Editor (included in Microsoft Office). The created equations can then be embedded inside other OpenOffice.
LaTeXiT is a 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.
Tex2Img is a free online Latex equation editor that converts Latex equations to high resolution images to embed in documents and presentations. You can also use Tex2Img to learn Latex by trial and error.