The link is: http://engcross.blogspot.com.br/ and his page in Google Play is https://play.google.com/store/apps/developer?id=Eng+Cross
There is following some screenshots presented in the page in Google Play.
App 4 View: applies 4 effects in your camera visualization, then you can select which you want, just touching on the screen, and take photos these are saved in SD card.
App Right Angle: transforms your Android device in a set-square tool, identifying right angles in the image captured from the camera, all you need to do is to put the mark over a 90° object, as a desk, table, draw, furniture, etc.
Other information, these two apps are free and without advertisement, so we can use them right now!