Experimente [esse app](https://play.google.com/store/apps/details?id=com.englishscore).  
O certificado emitido tem algum reconhecimento formal.

Segundo eles mesmos [no site](https://www.englishscore.com/):

>Certify your English level with a respected and accurate English certificate from the British Council.
>
>The world’s only mobile-proctored English test, EnglishScore uses the front-facing camera to monitor test-takers’ performance and deter against cheating.

Experimente esse app. O certificado emitido tem algum reconhecimento formal. Segundo eles mesmos no site: Certify your English level with a respected and accurate English certificate from...