These are really just a matter of convenience, but I think these are worth checking out the most:
Scripts:
Dashboard Progress Plus
Ultimate Timeline
Additional Resource Links/Stroke Order
Mistake Delay
Similar Kanji (though this site is a much more comprehensive method of looking for similar kanji: here)
Chrome Extensions:
Wanikani Notifier
Wanikani Companion
Apps (if Android):
Wanikani Mobile
I know people might throw in ones like Override, Double Check, Reorder, etc, just my opinion, you really shouldn’t need those. Good luck!
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