I created https://idorecall.com/ and it is different than apps like Anki. You upload your learning materials into iDoRecall. File types such as .docx, .pptx, .pdf, images files or add media share links from YouTube, Vimeo, Soundcloud, etc. You consume your content in iDR. When you come across a concept or fact that you want to remember, create a linked spaced-repetition flashcard. When you practice your flashcards, if you struggle with an answer, click a link to open up the source file or video at the exact location where you created the card. Refresh your memory and then get back to your practice session. Also, you can create study groups with classmates and collaborate, sharing files and flashcards. I have written about my background and story https://bit.ly/2Tp3vTr