This is a basic video demonstration of the stroke order rules for writing Chinese characters. It's short and if you find something lacking, your question may have already been answered in the comme... Read more.

youtube.com

This is the best overview of spaced repetition research I have seen online or offline. It's thorough, well-argued and probably covers more than you were looking for. It's not specifically about Chi... Read more.

gwern.net

You can input Charakters and this tool will output statistics about the words and characters, and can suggest high frequency words and characters that should be learned. It also analyses the HSK le... Read more.

hskhsk.pythonanywhere.com

A program to split any Chinese text into individual words, summarizing information about each unique word. The information is presented in the form of a tab-delimited matrix, so that the results ca... Read more.

zhtoolkit.com

There are currently around 80 videos here that introduces vocabulary and phrases in Chinese. They are mostly idiomatic expressions or other words that typically don't appear in textbooks, so that's... Read more.

youtube.com

This is a language learning game that features among other languages Mandarin Chinese (at first only Japanese was supported). It aims to teach you about 400 words by having a virtual character walk... Read more.

playinfluent.com

Online Chinese flashcards that adapt to your learning, Chinese speaking practice using voice recognition, and a simple, fast Chinese-English dictionary. Read more.

fastchinese.org