Woe betide he or she, who depends upon this application to learn English accurately. Clearly an effort on the developers' part to make a quick buck (much like the rest of the applications I've sampled from them), this application is low on content, has a small, ugly interface and does not even provide valid information all of the time.
Five different tests, i.e. sets of fill-in-the-blank questions, are available in the application, although there's no apparent reason for them to be separated as such, other than to make it appear as if there is more content. Within a test, questions are randomly and indefinitely chosen from a bank, causing them to repeat frequently. A percentage at the top of the screen tracks the accuracy rate of response, but it incorporates multiple answers of any type on the same question. The absence of a check mark is the only indication of an incorrect answer, and when there are multiple correct answers possible the application does not require them all to be chosen or otherwise highlight that the answers not chosen are not incorrect.
There's more wrong with this app than right, so avoid it at all costs.