The "Microsoft Translator" app that's in Google (@ "translate.Google.com") is full of grammar helps form many languages. However, with the Google app you have to do the work -- thinking, typing, highlighting when necessary (almost all the time), and entering your 'exercises'.
Here's an example of what I mean: I entered two simple English words ("mouse" and then "house") to determine the German articles for each English word, singular and plural.
input 1: a mouse. the mouse. that mouse. some mice. those mice
output 1: eine Maus. Die Maus. diese Maus. einige Mäuse. diese Mäuse
input 2: a house. the house. that house. some houses. those houses
output 2: ein Haus. das Haus. dieses Haus. einige Häuser. diese Häuser.
One doesn't have to repeat the words as I have done in this example. By 'computer magic' you can type the root word and its article once, then highlight and overtype the article with other ones to get new outputs.
You'll note that the Google translator not only output the correct article for the nouns' gender, but also capitalized the nouns, as they should be in German.
This particular exercise is an interesting example of Google's grammar inclusions. To see what I mean, all you need to do is highlight "Maus" and/or "Haus" -- and see what you get. It's a very good learning exercise.
Those who publically disparage the Microsoft translator app in Google really don't know much at all about the app, and also not its impressive language translations, but its interpreting of the translated output. By this I mean that the output translation is not word-for-word, but is a rendering in colloquial English.
Lastly, a Google translator feature that I've found to be highly useful is its fast/slow two-speed pronunciation of input text. The 'fast' speed is normal speech, the 'slow' speed is slow enough to hear distinctly the pronunciations of words, phrases, sentences, etc. In other words, as you study the German articles you can hear them distinctly pronounced.
I know quite a lot (but not everything, of course) about the Microsoft translator app -- I have been using it's Google application every day for the past four months doing a tri-lingual translation (German, English, and Berlin dialect) of an old German joke book.