IntroStat is a free, feature-rich probability and statistics calculator for Android, designed to cater to the needs of introductory statistics courses. It offers a comprehensive set of tools to perform various statistical calculations, including generating summary statistics, calculating z-scores, drawing box plots and histograms, visualizing key concepts like the empirical formula, plotting discrete and continuous random variables, conducting hypothesis testing, computing confidence intervals, and much more.

The app also includes an introductory statistics textbook, complete with formulas, exercise problems, and examples to help students understand the subject better. The app's user interface is straightforward, making it easy to navigate and perform calculations. Users can enter and save datasets, perform probability calculations, and look up critical values of distributions.

For premium users, the app offers additional features like dark mode, 12 color themes, zoom, custom decimal precision, comma display, and no ads. The app's privacy policy and end-user licensing agreement are available on their website.

Overall, IntroStat is an excellent tool for students and professionals alike who need to perform statistical calculations on the go.