Starting life as a simple ‘doodling’ utility (hence the name), iDoodle has grown to become a rather function rich graphics application. In fact, given that Apple themselves haven’t written anything similar for the touch-screened iPhone, I’d tentatively suggest that they license iDoodle to put in the next iPhone/iPod Touch firmware – it’s that good. In point of fact, it’s NOT perfect, as you’ll see below, but there’s still an awful lot to impress.

So. It’s a touch-driven painting utility for the iPhone. You’re probably imagining most of iDoodle’s functionality right now – and you’re right, the basics of brush, line and shape drawing are all here, in a cornucopia of colours. There’s even a free ‘Lite’ version of the application which already does all this. But iDoodle 2 goes a lot further. A Text tool means that you can overlay text (at any font size) onto your creations, a ‘Blob’ tool automatically closes the shapes you sketch and fills them with your chosen ‘fill’ style, and so on. You can set the current outline and fill styles from the bottom of screen toolbar and, impressively, the fills are all graduated – in fact, you have to work extra hard to NOT have them graduated (by setting both ends of the fill to the same colour)!

Although clearly not in the Photoshop class, there are some semi-pro features here, such as being able to set the opacity on anything you draw, i.e. the degree to which the background is allowed to show through. With some artistic skill (I have none!), it should be possible to get some striking effects. Handily, there are two ’save’ modes. The first saves to iDoodle’s own Gallery, from where you can retrieve sketches later for adding to them, the latter saves (finished) masterpieces to the iPhone’s Photos gallery, from where a picture can be emailed on, for example. You can also bring photos from the standard iPhone photo store into iDoodle, to be used as a background, a very neat trick, as seen here in the sunset example.

But the standout feature is the innovative use of the iPhone’s accelerometer to activate the unlimited ‘Undo’/'Redo’ function. Unhappy with your last brushstroke or shape? Simply waggle the device to the left by 90 degrees or so and then rotate it back again. Your last action is undone. Similarly for extra ‘undos’ and for ‘redos’ (waggle to the right, of course). At first, I thought this was a gimmick, but it’s actually intuitive and fast. A related function is being able to animate through your additions to each image, one at a time, producing a neat stop-frame animation ‘building’ effect.

My only beef with such a great utility is that there are usability issues with its sliders. These are used a great deal for adjusting colour values and tool thicknesses, but don’t always respond to a finger tap or drag and it can be quite frustrating dragging over and over again, until the action is finally taken on the umpteenth try.

A minor bug though, and one which will surely get dealt with. iDoodle is a classic of the iPhone App Store and deserves all the recognition it gets.