I've been using Anki for learning foreign language words for at least 2 years during my commute. At the start of using flashcards I could learn near 20 words for a day, but now, based on my experience, the number of learned cards decreases. At the same time repeat learning helps me do not forget words which were learned a year or so ago and rarely used. I also noticed, for me, the best approach for better remembering is practicing during the morning commute. It became my everyday routine :)

Using Anki is very helpful if you need to repeat much information for a small period of time, e.g. before exams or interviews.