Some good, some not so good.

Good
This app is beautifully designed, has zippy navigation, and functions great.

Not so good
There are grammar errors in a number of the questions in additon to punctuation problems, poor sentence structure, and weak word choice. I am not the language police (there are probably errors in this very review), but it is ironic and disappointing to such problems in something that people use as an educational language tool.

This app is so beautifully designed. I am hopeful they care enough to fix the content.

Letmeguessthisnicknameistakentoo about Grammar Up : 1800 Questions