iPad App Store is open

iTunes has a number of them available for purchase, though you obviously can't use them without the gadget itself, which doesn't go on sale until Saturday. So far, there are more than 2,300 iPad apps, with many more being added by the day. Among the niftier ones mentioned by Digits:

--Autodesk SketchBook Pro, a paint-and-drawing application, is $7.99.

--ABC Player app is free and saves your place in a video episode.

--The Omnigraffle iPad app, at $49.99, allows users to create quick diagrams, charts and designs.

--NPR app is free and allows users to read stories, in a magazine format, while listening to audio.