The first thing to note is that they overhauled the entire drawing engine, so it works the same across every platform. Also, a 100 Megapixel Canvas, practically unlimited layer support, and a big undo/redo stack.
The Rapid UI, as they call it, is the refinement of their intention to keep the canvas as clean as possible without losing the usability. If you're using a tablet, the UI will appear when you drop your non-dominant hand on the screen. If you run your stylus through one of the menus that sit on top of your canvas, it will wink out of existence until you’ve passed through the menu entirely. There's also the center-bottom quick menu that you'll use most of the time. It's there to call it up when you need it, but it doesn't bother you at all while you're working.
Now you have brush textures in addition to shapes. SketchBook for Android now comes with 60 new default brushes, which you can then customize to your liking.
In the Smart Assistive Technologies department, there's a new Ruler and Ellipse Guide. You can draw ellipses in perspective by adjusting the position, size, rotation, and aspect ratio of the guides. This sounds like simple stuff, but they are those things that you use constantly and make your life so much easier, so they are essential. But the one addition I particularly love is the Predictive Stroke. Of course you can turn it off if you're expressively painting. But if you're designing, for instance, it's an amazing aid!
I come from desktop software with many keyboard shortcuts, so it took me a minute to get used to not having that. But once I spent a little time inside the program, it was so easy to get in the zone and paint vigorously for a long time, to the detriment of my badly positioned neck, that ultimately suffered the consequences of my enthusiasm. This does not happen with all software, but only with programs that are written with the user and their needs in mind. This characteristic is what I find makes SketchBook shine, and the Android version is no exception.
Some of my favorite features are:
- Scan Sketch. The name says it all: it lets you scan a sketch with the device's camera and if you want, it makes the white background of the paper transparent, so you only have your drawing to deal with.
- Tap and hold on any point and it activates the Eyedropper Tool. Then you drag until you find your color, then let go, and the color gets selected. This is what I mean about usability. Great!
- The Transparent Color feature, that turns any type of brush you're using to an eraser, so you can add and subtract with the same nib settings while you're painting.
All in all, it's a great, very useful app for sketching, painting and designing on the go. Now considering this huge upgrade they did for the version 4, it feels as complete as the desktop version, but tailored and tweaked for the different mobile devices.