The most four English proficiency test that is widely-accepted: TOEFL, IELtS, CAE and CPE which test your English vocabulary level and your grammar.
C level is the most important level required in many fields, such as entering universities
Meaning test app gives you an opportunity to test your understanding of the words of this level. It is very simple, it gives you the meaning of the word and you are required to choose the right word.
Repeat the test many times as you like to memorize the meaning of the word.