Duolingo, Rosetta Stone, Anki, RemNote, LingQ, Memrise, Learning with Texts, FLTR, Corgi AI, UneeBee, Wisdolia, Lingua.ly, SmartCards+, FlashRead, Lingro, paralleltext.io, Aprelendo, LingoDream, Lingocracy, Languages Online, TenWords, Wordswing, Slowmersion: Chinese, LingoZING! are some alternatives to Readlang.