I was on the fence about this one as there is currently another "blur" app on AppSumo and I wasn't sure this one was worth the extra money. Because of this, I ended up getting both.

DataMask is slick. It has a nice interface and it does what it says. It also gives you lots of options for securing your data.

1. You can manually edit text, before blurring.
2. You can completely remove screen elements.
3. You can use the Blur+ option, which scrambles the words/image and then blurs everything in a single step.

Everything you do on a screen "sticks" until you remove it, so if you're doing a live presentation where you need to show up-to-the-minute (but blurred) sites, you can pull them up with confidence.

In addition, there is a nice image editor included, which you'll have access to once you do a screenshot and will let you put pixels over certain parts of the screen or black it out completely.

I also like the up-front way Tomas has answered questions. It's nice to see developers who don't back down from "hard' questions or get agitated/defensive about them.

I'm keeping this one.