Apps-on is another great tool for sketching out your iPhone ideas. It’s true to size and shape to the iPhone 4 and comes with a dotted grid system that disappears when scanned or photocopied.

Here’s a list of free iPad templates and stencils that we’ve been using at Ideacodes to get you started:

iPad Stencil for Omnigraffle by iA

• Contains backgrounds, title bars, buttons, selectors, and other iPhone UI elements
• Text is fully editable on lists, title bars, buttons, and scroll wheels

iPad PSD GUI by Teehan + Lax

• The PSD was constructed using vectors, so it’s fully editable and scalable.
• The workable screen design is formatted to 768×1024 so anything you design in the Photoshop file can easily be brought over to the SDK.

iPhoneOS Design Stencil for iPad and iPhone by David Morford

• A stencil for designing iPhone OS applications for iPhone, iPod touch and iPad devices.
• Targeted at developers familiar with the default characteristics of views and controls provided by UIKit.
• The stencil shapes are all vector based.

iPad editable PSD by Kevin Andersson

• Every element you see is editable via vector masks.
• Everything is scaleable.

iPad Wireframe PSD by Neil Cowburn

• Minimal wireframe version of the iPad without the photorealism

iPad Icon Set by Chris Spooner

• The pack includes the full size graphic, as well as 256px, 128px and 64px icons sizes.

Printable iPad Template PDF by Arash Keshmirian

• The PDF is set up to print very closely to scale with a real iPad. Just make sure any options like “scale to media” are off, and the PDF is printed at 100%.