I had not realised it was in Android proper, I have only seen it in Cyanogenmod. I wonder if it wasn't used more because people didn't know about it, and didn't

I had not realised it was in Android proper, I have only seen it in Cyanogenmod. I wonder if it wasn't used more because people didn't know about it, and didn't realise how much safer it was. Sad that they removed it.