Rather than using Google Translate, it is better to set up the Japanese keyboard on your iPad. Most of the people type with a romaji keyboard either way, so even if you are not familiar with hiragana yet, feel free to use it. Below is a guide about how you install the Japanese keyboard.
Go to “Settings” and tap “General.” It's in the third grouping of menu items for me.
Select “Keyboard.” ...
Tap “Keyboards.” ...
Select “Add New Keyboard.” ...
Tap “Japanese.” ...
Select “Romaji” (or “Kana” if you want to type in hiragana directly) and tap “Done.”
If you wish to "draw" a character in, yes, you can do so in Google Translate, it recognizes characters very well. But by itself Google Translator is definitely one of the worst choices to learn Japanese by.
About writing characters: every kanji has its own recognizable components, each being written with a certain order of strokes. Learning the order helps memorizing kanji big time plus this way you are able to recognize handwriting much more easily, as you already know the "flow" of each character. Google Translate doesn't provide you with this.
About the readings given in Google Translate: you are presented with a single reading there, while most of the kanji have multiple of them, let alone the presented reading may be erroneous (I have encountered this at least a few times).
About the meanings provided in Google Translate: while the built-in translator's dictionary (which isn't very large, by the way) shows you some of the meanings, the full list is usually significantly vaster, plus you won't learn the nuances.
If you come across a character that you don't know and that you can only roughly draw, feel free to draw that character into Google Translate, but after that, if you want to learn the meanings, readings, and order of strokes of the kanji, please, copy it into a dedicated application like Kanji Study (it's free if used as a dictionary), or an online dictionary like Jisho.org. There are many other options around, however, both on mobile and PC. Don't hesitate to explore.