Here are some things I’ve made that Chinese learners will find useful:
Chinese Text Analyser - helps you find Chinese content suited to your current vocabulary level and then prioritise which words from that content you should learn
Hanzi Grids - lets you generate custom Chinese character worksheets for handwriting practice
Pinyinput - makes it easy to type pīnyīn with tone marks in any application
100% - an iOS app for developing good habits and keeping you on track to achieve your goals