It doesn't matter whether the dashboard was built in Tableau, Power BI, or Looker — the reason it's unreadable on a phone is almost always the same: it was designed for a wide screen and never redesigned for a narrow one. The tool-specific features (Tableau's Device Designer, Power BI's Phone Layout, Looker's responsive tiles) all help, but the actual work of making a dashboard mobile-friendly is a design process, not a checkbox. Here's that process, independent of which tool you're using.

Step 1: Audit what's actually on the dashboard

List every worksheet, tile, or visual on the dashboard and note, for each one, whether someone has ever made a decision based on it while looking at a phone. In most audits, a 15-tile executive dashboard boils down to 4 or 5 numbers that people actually act on — a revenue figure, a conversion rate, a count that's trending the wrong way. Everything else is there for completeness on a desktop review, not for a 30-second phone check.

Step 2: Rank metrics, don't just shrink them

The instinct is to keep everything and make it smaller. Resist it. A phone screen has room for a clear hierarchy: 3–5 primary KPIs at the top, a handful of supporting trends below, and everything else left on the desktop version where there's room for it. If a metric doesn't change a decision on its own, it doesn't need to be one of the first things someone sees on their phone.

Step 3: Match the visual to what the number needs to say

Desktop dashboards favor dense chart types — clustered bars, multi-series lines, crosstabs — because there's room for axis labels, legends, and multiple series side by side. On mobile, three visual types cover almost everything you need:

  • KPI card — the number itself, a delta versus last period, and a direction indicator. Use this for any metric where the current value is the point.
  • Sparkline — a small trend line with no axis clutter, attached to a KPI card. Use this when the trend matters as much as the current value.
  • Simplified bar or ranked list — top 5 items, single series, labeled directly instead of via a legend. Use this for "what's driving this" breakdowns.

Almost any desktop chart maps to one of these three once you decide what question it's actually answering.

Step 4: Design for tap and glance, not hover and study

Anything that currently lives in a tooltip needs a new home, because there's no hover on a touchscreen. Either put it directly on the card as text (the delta, the comparison period, the unit), or accept that it's a desktop-only detail. Also design the interaction model around a single tap per screen — tap a card to drill in, tap back to return — rather than the multi-control filter panels common on desktop dashboards.

Step 5: Stack vertically, always

Desktop dashboards use columns because there's horizontal space to spare. On mobile, any multi-column layout either forces horizontal scrolling or squeezes each column into an unreadable sliver. A single vertical column, ordered by the ranking from Step 2, is the only layout that reliably works across phone sizes without a horizontal scrollbar.

Step 6: Test it on an actual phone, not a resized browser window

A resized desktop browser window is not a substitute for a real device — real phones add glare, one-handed use, notification interruptions, and actual finger-sized tap targets. Before calling a mobile layout done, open it on a phone, hand it to someone who didn't build it, and watch whether they can find the one number they came for in under ten seconds.

Doing this by hand doesn't scale past a handful of dashboards

This process works, and it's exactly what Device Designer, Phone Layout, and similar tool features are trying to help with. The catch is that it's manual, per dashboard, and has to be redone every time the underlying report changes. For one executive dashboard, that's a fine one-time project. For the 30-plus dashboards a real BI team maintains, it turns into permanent upkeep on top of the actual analytics work.

Datavizium runs this same process automatically: point it at an existing Tableau, Power BI, or Looker dashboard, and it reflows the metrics that matter into KPI cards, sparklines, and simplified charts your team can open from a link on any phone — no phone-specific layout to build or maintain by hand.