Since the iPad was launched, I’ve been curious how this device would be adopted as a working tool by the UX community. Apart from the many project management, mind mapping and sketching apps, there are also a few diagramming apps available for the iPad that could help with creating wireframes and flow charts.
OmniGraffle is one of the most popular diagramming tools for Mac, and it’s therefore natural that the OmniGraffle iPad app has received some attention among UX professionals. However with a price tag of £34.99 (as of November 2011), it’s one of the most expensive iPad apps and far more expensive than alternatives such as the popular iMockups app.
The welcome page is an actual diagram document and works as a tutorial explaining how to perform common tasks.The user is asked to touch, hold and drag objects, draw a line etc. to familiarise with some of the key features(see image 1). This is helpful because the app really has many features.
The app comes with a few ready-made diagram examples. These examples showcase what can be produced using the app; from detailed to freehand drawn wireframes, as well as various organisation and flow charts.
When opening a new canvas, the interface looks simple with only six buttons at the top of the screen. Initially, the simple design inconvenient when designing for a tablet touch screen device since the real estate is limited and buttons must have a minimum size so that they’re easy to tap.
The icons used on some of the buttons aren’t particularly descriptive about what lies behind them but it’s relatively easy to learn the key options of the application. If you’re familiar with other types of diagramming software, it won’t take you long to familiarise with the navigation and locate the most common features.
Using the drawing canvas is easy. Diagrams are created either from ready-made objects in the stencil library or via freehand drawing and it’s very convenient having the option to combine the two methods. Whereas freehand drawing makes it easy to capture initial ideas, UI objects from the stencil library help illustrate the details, which can be difficult to draw by hand.
The app also has a useful ‘connectors mode’ for creating flow charts. The mode makes it easy to connect boxes with a ‘snap to object’ function, and with a bit of practice you can make some detailed and professional-looking flow diagrams.
It’s also easy to select multiple objects and move or group them. Here, OmniGraffle does better than other diagramming apps that I’ve tried on the iPad, where manipulating objects can be quite clunky.
Like with the ‘connectors mode’, the app has a ‘snap to grid’ feature making it easy to align objects. If it’s still difficult to place a single object in the right position, it can be moved pixel by pixel via arrow keys from the formatting palette.
The app has a stencil library with a huge selection of objects, making it possible to create detailed diagrams. The library contains the most common UI objects for web navigation, forms, buttons, social networking features and icons. However, it contains so many objects users will have to spend a lot of time scrolling through the lists. It’s lso sometimes difficult to identify some objects because the thumbnails are too small. Often, you may have to drag an object to the canvas just to see what it is (see image 2).
After using the app a few times, I became familiar with the stencil library and I found myself using only a small amount of the objects available. I wouldprefer a smaller selection of objects and less scrolling. After all, this is an app for sketching and capturing ideas – if I wanted to do detailed wireframes, I would use my computer.
Another problem with the stencil library is theloading time. In particular, the ‘Konigi wireframes’ library loads very slowly (more than 10 seconds on an iPad1), and since this library contains most of the UI objects it really has negative impact on the user experience.
I’ve never experienced such delay in any app on the iPad before. Whereas the problems with the number of options in the library probably decrease (or can be avoided) over time when familiarising with the app, the loading time is a significant problem interrupting the user flow, especially when you want to sketch some ideas ‘on-the-go’.
Similar to the vast selection of objects, the app has an enormous amount of features. Objects can be manipulated in any way you can imagine. The app has most of the formatting options I would expect of a full size desktop application, but it delivers much more than what I would expect of an iPad app. With the OmniGraffle app, I can create diagrams that look much better than with any other diagramming app for the iPad I’ve tried.
However, since all the features and formatting options are hidden away in menus and toolbars, it takes a lot of tapping to get to them and is prone to errors. The complexity slows down the drawing process and makes the app less suitable for quick sketching.
An additional problem with all the menus is that their positions are fixed and they overlap parts of the canvas. If the selected object is located under a menu, you can no longer preview how your formatting changes the object. A formatting palette e.g. located in the right column would have been preferred, perhaps with a show/hide function so it doesn’t take too much real estate.
The OmniGraffle app for the iPad is a good tool for creating freehand sketching and makes it possible tocreate more detailed and better looking diagrams than other iPad apps that I have tried. After using OmniGraffle for this review, I went back to iMockups, which used to be my preferred tool for wireframing and I found myself missing the features for creating masters, managing layers and the easy multi-selection options. The diagrams just look more professional with the OmniGraffle app!
But the many features does have a negative impact on the usability of the app, and it really slows down the drawing process. Also the significant delays when loading the stencils libraries are problematic for an app made for creating quick diagrams and capturing ideas ‘on the go’.
Therefore, the question is whether it’s worth spending the extra money and time having all the features. If you use OmniGraffle on a Mac, it can be useful because you can export the diagrams you’ve done ‘on the go’ to your Mac and continue working from there. Unfortunately, the only other format available for exporting is PDF, so users of other diagramming tools are limited to using OmniGraffle for iPad as a sketching tool. For this purpose, iMockups and other diagramming apps, which cost much less of the OmniGraffle app can do the job.
What do you think? Have you used any other apps in a UX capacity? Let us know in the comments below!