Whichever app or website you end up using for your purposes, i still recommend to follow along with the website Toritoribe provided the link for for reference. The reason being you may end up memorizing obsolete stroke order, or even worse Chinese version of a kanji. Some websites and apps seem to use fonts with obsolete forms of kanjis. Take a look at this kanji for example
「溢」の書き方 - 漢字の正しい書き順(筆順) It may be displayed as the one on the right in your app, while correct modern Japanese kanji is the one on the left.