My organization has, until my hiring, been of the mindset that we should present identical user interfaces and experiences whether our users are interacting with workbooks on their desktop/laptop computers or on tablet devices. The design part of my brain immediately started shooting up red flags (the first of which was "Where do we draw the line? Present the same dashboard on a phone? A smartwatch?"), so I started writing a list of ways I think designing for a small form factor (particularly a touchscreen device) should be approached differently. There are certainly ways to optimize a workbook for touchscreen devices, and I'd love any additional feedback that could help me make a case for the importance of breaking out of this mold.
1. Be concise. While a 4 pane division may be fine on a desktop device, the limited screen real estate of a tablet carries with it a different "sweet spot" for impact. Perhaps 2 or 3 panes/visualizations may be more effective, depending on the data and its meaning. As Eric Shiarla of Interworks once said, "Our goal in any data analytics project is to provide insight into our data. Our effectiveness at doing so decreases as our dashboard becomes more complicated and difficult to decipher."
2. Start big, drill small. More tabs can always be created, and redirect actions could be more conducive to touch screen drilldown than contextual menus. Tabs/additional dashboards should be arranged logically, with relevant drilldowns located in proximity.
3. Avoid any use of hover tooltips. Line graphs can benefit from informative drop lines if there is sufficient sizing, but without the use of a mouse hover tooltips/actions are going to be too inconsistent to be dependably used.
4. Use color appropriately and sparingly. Maximum contrast will occur when color is used to highlight. Having a color scheme with 5+ colors becomes difficult for our brains to retain. Conveying meaning like top-n or beyond a threshold is an effective use of color.
5. Select the right viz for the data and its context. Changes over time will almost always be best shown with a line graph. Division by category will usually be most effective as a horizontal bar chart. Pie charts and packed bubbles are almost always the wrong choice, for a variety of reasons. Sparklines are powerful and design simple, but must be presented alongside context.
6. Remove clutter. If a category is already labeled in the chart, perhaps there's no need for a color delineation as well. Showing a graph and its corresponding crosstab can be acceptable, but only in certain circumstances and only in proximity to one another. Text, like color, should be used concisely and presented simply.
7. Keep an eye to performance. Especially with mobile devices, a simpler workbook will function faster. If there are fields not in use, consider not pulling them through to the final product. If users don't care about a particular metric, do not use it. A dashboard that presents entirely too much information is like trying to convince your users to drink from a firehose; it is both inefficient and jading. Having to divide their attention leaves much less capacity to focus on what really matters.
Do you need to present similar workbooks or dashboards tailored to mobile devices? What's your design thought process?