The best and kindest way is still telling it to the person's face.

I think this is super. Talking face to face may be the best and kindest way, but getting it said one way or another is what really counts. The easier it is to communicate for a wide variety of people, the more it will help the overall population.
These might be great for teens. If they can't bring themselves to insist on a condom, they won't be able to talk about it after the fact, either.