Sketchpad Explorer for the iPad is a free app, available in the iPad App Store. Go to the App Store on your iPad, search for "Sketchpad Explorer," and download it.
Sketchpad Explorer allows you to explore any sketch created by Sketchpad itself. You can explore sketches from Sketch Exchange, sketches on the web, sketches you receive by email, or sketches you create yourself.
Explore Sketches from Sketch Exchange: In Sketchpad Explorer on the iPad, press the Documents button at the lower right and choose the item to visit the Sketch Exchange community site. The site appears in Safari. Browse through the sketches there, choose one, and press the Download button. A choice will appear asking which app should open the sketch; choose "SketchExplorer." The sketch will then open.
Explore Sketches from the web: Using Safari on your iPad, browse to a page that contains the link to the sketch you want to open. Press the link for the sketch, and a choice will appear asking which app should open the sketch. Choose "SketchExplorer," and the sketch will open.
Explore Sketches from email: When you receive on the iPad an email with an enclosed sketch, you can tap the sketch and then choose to open it in Sketchpad Explorer.
Explore Sketches you create yourself: Attach your iPad to your computer so that iTunes opens, allowing you to sync your iPad to your computer. Select the attached iPad in the Devices section on the left, and then click the Apps tab in the iPad main window that appears. Scroll down to the File Sharing section of the page, choose SketchExplorer in the Apps panel, and drag the desired sketches into the SketchExplorer Documents panel. Once iTunes has finished synchronizing the data to your iPad, the sketches will be available from the Documents button within Sketchpad Explorer.