Survey Monkey - Create and publish online surveys in minutes, and view results graphically and in real time. SurveyMonkey provides free online questionnaire and survey software.

Sum Fun - A fun number puzzle game for iPhone and iPad.

Typeform - Create beautiful, next-generation online forms with Typeform, the form & survey builder that makes asking questions easy & human on any device. Try it FREE!

HoDoKu - HoDoKu is a sudoku helper written in Java and available in English and German.

Google Forms - Simple web forms from Google.

Math Master - Brain Quizzes - Math Master is a free math quiz game designed for all ages!