And not just with brush, you get a whole set of mask editing tool. √ Layers support all that a true layer app should. Blending, Opacity, Transform, Duplicate, Merge and flatten. √ The app is so fast that most of the operations are real time. You don't have to wait while adjusting the sliders. √ Handles Exif, IPTC, Geotag etc. You can even edit Geotag and IPTC. √ Exports PSD with layers. And of course exports JPEG and PNG too. √ Copy/Paste with selections and masks. √ Undo/Redo. √ Powerful filters you will hardly find on many other apps. √ 25 preset photo effects. √ Tools like Crop, Straighten, Clone stamp, color gradient, paint brush, red eye brush and add text etc. √ You can save your projects with all layers and selections preserved and work on them back and forth. √ 18 video tutorials. √ Resolution up to 4096x4096 on iPad3 and above and on iPhone max resolution is equal to the resolution of the built-in camera. And yes, it runs on both iPhone and iPad. Note that reduce noise filter is available only on iPhone 5 and iPad3 and above. To get maximum resolution you will need to... 1. Go to home screen. 2. Press on the "?" button. 3. Under resolution, select the max.