Layers最多可添加5个图层，可以选择显示层或者隐藏层，还可以建立几个透明图层对图片进行编辑，最后可以重复或者合并层。

Features:
- A clean, intuitive painting interface
- Two fingered pan and pinch to zoom
- Double-tap for quick zooming
- Square and 3:2 rectangular canvas sizes
- Ten high-quality brushes
- Up to five paintable layers per drawing
- Paint brush, smudge tool, and eraser
- Full featured eyedropper tool
- Precisely adjustable brush sizes up to 64px
- Large color picker that saves recent colors
- Full support for brush transparency
- Generous undo history that is saved on exit
- Email as JPG or PSD file with layers
- Replay drawings using Mac OS X viewer
- Export high-res drawings using Mac OS X viewer

What's New In Version 2.4.1

Version 2.4.1 greatly improves support for the iPhone 4. iPhone 4 users can now create larger drawings - up to 1024x1024 with five layers! The application also takes full advantage of the high-resolution retina display.