Mobile Interaction Metrics: Addressing the ‘Fat Fingers’ Problem

As we kick off the year of mobile measurement, it’s especially critical to consider the state of measurement of ad interactions. Interaction rates are an important category of engagement metrics, and a vital way to judge whether creative and media plans are working. There are two big challenges to this aspect of mobile measurement:

  • The need to avoid the easy, least-common-denominator “click-through” as the metric of choice, in favor of metrics more reflective of the array of interactions in mobile.
  • The need to make sure that the numbers are trustworthy and reliable.

Problem two is serious: one widely quoted statistic says that up to half of mobile ad interactions are accidental – due to “fat fingers” rather than actual consumer interest.

Establishing guidelines or best practices for mobile ad interactions will be a long-term project. But the outline of such a guideline is predictable. Interactive Advertising Bureau (IAB) measurement guidelines (including the IAB, MMA, and MRC’s mobile web ad measurement guidelines) are long, technical documents, but at their heart, they always do two things: establish what to measure, and then describe in detail how to measure it.

The list of mobile interactions to measure is lengthy and evolving. Cataloging and rigorously defining all of the myriad types: swipes; views; shakes; orientation changes; expands; tap-to-calls; tap-to-maps; and so forth, ad infinitum (and, yes, plain-old taps/clicks too), is a challenge. It’s easier to say something about how to measure than about what to measure.

Across all digital ad measurement guidelines, certain principles about how to measure are, to borrow a phrase from the Media Rating Council (MRC), “motherhood and apple pie.” Whatever the digital ad interaction may be, a key motherhood-and-apple-pie principle is that only actions performed deliberately by a human being should count. Thus, automated systems that generate clicks or taps or other interactions need to be cleaned out of the data, and so do interactions that the user did not intend. Weeding out accidental interactions is going to be particularly important in the smartphone and tablet world: probably everyone who has used the mobile web or apps for any length of time has run into the “fat fingers” problem.

There are several ways to ensure that an ad interaction is deliberate. One possibility is to change the creative design to make accidental interactions less likely. For example, when someone taps on an ad, the ad could request they tap again to verify their intention. Google’s AdMob recently announced a mobile banner offering called Confirmed Clicks that does this. Similarly, since unintentional swipes are much less likely than accidental taps, an ad unit could require a swipe to initiate interactive elements or go to a landing page. Tremor Video’s Super Mobile Video unit works this way.

Another way to filter unintentional interactions would be to set a minimum interaction time threshold. Anyone who accidentally interacts with a mobile ad will correct their error fairly quickly. So by timing the length of an interaction, a server can exclude from the count any interactions under a minimum duration. This doesn’t change the user experience (fat-fingered taps still happen), but it does mean that advertisers aren’t charged for the mishaps.

Without endorsing any particular approach at this point, I do believe we need to start improving mobile ad interaction metrics, particularly doing more to filter out accidental and non-human interactions. Sellers should be more transparent about how they do this, and buyers should insist on it. Five years ago, PC web advertising faced a growing backlash against “click fraud” before industry efforts – including IAB’s Click Measurement Guidelines – established a bedrock of better counting principles. Searching on “tap fraud” today reveals problems with Oktoberfest, not mobile advertising. That’s fortunate, and we need to keep it that way.

Man Using Mobile image on home page via Shutterstock.

Related reading