A Corrective Concealer or Colour Corrective Concealer is a make up product designed to change the undertones of your skin colour before you apply make up. The most famous example of colour corrective concealers in action is this image posted by Kim Kardashian on twitter (@) while getting her make up done.
These concealers are a wonderful way to blend in and hide any bruises you might have. Just covering a blue or purple bruise with a flesh coloured concealer is not enough. What you want to do is correct the undertones of your skin before you apply any make up at all. I was a little skeptical at first but they won me over in the end.
I now use colour corrective concealers under and around my eyes, as they tend to be the first places to darken into bruising when my platelets are low.