Tsurukame is great. I think my two favorite features are the one to allow marking as correct and being able to download all the audio files at once for almost no lag to playback after answering a review.
The updates are here: [iOS] Tsurukame - native app with offline lessons and reviews - #656 by UInt2048
One thing to note is that because it’s an app, there will be a delay when they add a new item. For eample, it doesn’t have 広がる yet, so you’ll need to make sure you catch the reviews for that one on the website.