I personally spent the $25 on the iphone app and I think it was probably the best 25 bucks I've ever spent. I rarely spend money in the app store, I think its usually a waste but having Anki accessible mobile was a game changer. I expect if I get into med school it will continue to pay dividends. If you have an android, I believe its free so for sure download it. Like Zenabi90 said though don't waste money on premade decks, the best way to learn is to create your own decks. If you're in a time crunch and don't have time to make your own cards than theres lots of free decks over a variety of subjects that can be found on SDN or on reddit MCAT forums.