Quite a few dating websites and apps are using personality tests to pair users who have complementary personality types together, as to increase the likelihood of finding a "perfect match". I see the Myers-Briggs Personality Test frequently being used, and users have testified the success of the technique. 'Research' funded by eHarmony claimed that 1/3 of married couples in the US met online.
I think it's interesting trying to evaluate our partners to see if they match up to what we perceive as 'ideal'. Whenever we do find a partner that is ideal (personality wise), then we might have greater satisfaction in our relationship.
To take the test you will need to know your own personality type, and have an idea of what your ideal (or dream) partner would be like.
My personality type: INTJ
My ideal mate: INFJ