Anki is a multi-platform flashcard system using #spaced repetition and Retrieval Practice to help the user better remember flashcard memory units.
Unlike #RemNote, it does not sync to a note taking system nor does it contain a hyperlinking system between cards and notes and so does not Link ideas for better retention. However, Anki is a well-established platform with many publicly shared decks and plug-ins available. Anki also has embedded sharing options within Android for easy construction of new cards. For these reasons, Anki remains my flashcard system of choice because Making it easy is better than making it powerful.
I have built up my use of Anki over time, from initial skepticism to daily practice. I use a combination of shared decks and self-constructed decks.
Because Anki is better suited to memorising individual units of knowledge rather than constructing new understandings, my main use for it is for vocabulary building.