There are little apps that are nice to have on your iPad and Inkflow is one of them. This free app is a basic drawing app for iPhone and iPad that is great if you want to sketch, capture your signature and then easily send or share it (as jpg or pdf) or save it to your camera roll. The app is very straightforward to use and when you download it it has a file waiting inside the app for you which tells you how to use it.
Once you have drawn or written something you can move and resize your selection and zoom and pan around the canvas as needed.
You can write, draw, insert text and photos and more. I've put a few screenshots here so that you can see the interface.
If you like Inflow then there is a big sister app, Inkflow Plus which has extra features (colours/more pens/more fonts/PNG export, rotate, cut, copy, paste). I have this but it certainly isn't cheap at £5.49. I like having these extra tools (see screenshots below) but, for a basic drawing app the free Inkflow is worth checking out for quick doodles.
There are lots of apps that try to fill this space. Inkflow is just the one that I happend on and continue to use. If you have apps that do a similar job that you would recommend, please do comment and let me know! :-)