Stroke order, animated with pinyin above or below, full sentences can be entered and displayed at once:
https://www.chineseconverter.com/en/convert/chinese-stroke-order-tool
bonus: here a video about how to expand the animation box to shore more character animations
Count the number of Chinese characters in a text, minus Chinese keyboard punctuation (。，：！？etc.):
https://www.chineseconverter.com/en/convert/chinese-character-count
Look up Chengyu idioms
https://www.chineseconverter.com/en/convert/chinese-chengyu-idiom-lookup
All about Chinese names
https://www.chinahighlights.com/travelguide/guidebook/chinese-names.htm
AI tools
Turn text into different natural sounding voices to study from, and build your ear for natural speech
https://www.naturalreaders.com/
Increase reading speed by reading similar responses and check your cultural knowledge with LLMs