In most online surveys, most respondents open the link on a mobile phone, even when the invitation is sent by email. Yet many questionnaires are still written as a document for a large screen and checked on a phone only before fieldwork begins.
The results are familiar: wide grids that require sideways scrolling, small buttons, open questions that ask for a full paragraph, and respondents who drop out halfway or click through just to move on. The damage goes beyond the completion rate. Those who stay give weaker answers, and those who leave are not a random group: they are often younger people, or audiences who go online almost only from their phones, so the representativeness of the sample suffers as well.
The principles
Designing for mobile means the questionnaire is built for the small screen from the start, and the desktop is the simple case. In practice it comes down to a few rules:
- One question per screen. Long introductions are split, and every question is shown on its own.
- No wide grids. Instead of a grid of seven statements on a five-point scale, statements appear one after another, with a vertical scale.
- Large tap targets. Answers in a vertical list with room for a finger, and no sliders that are hard to aim.
- Little typing. Open questions only when they are needed, with a short note on the expected length.
- Fast loading. Light images and videos, because not every respondent is on Wi-Fi.
- Easy to resume. A respondent interrupted halfway returns through the same link to the point where they stopped.
Testing on real devices
A desktop preview is not enough. Before fieldwork we go through the survey on several phones, Android and iPhone, with small and large screens. We also check what happens when the link opens inside WhatsApp or Facebook, because the browser built into those apps behaves differently from a regular one.
Then comes a soft launch with a small sample, where we check completion time by device type and the point at which respondents leave. A question where drop-off rises is fixed before fieldwork continues.
A questionnaire designed for mobile improves completion rates and answer quality among desktop respondents as well.
The benefits
A higher completion rate, shorter completion times and cleaner data, with fewer respondents giving the same answer down an entire grid. In addition, a more representative sample, because audiences who answer only on their phones do not fall away.
In all of our questionnaires, design starts on mobile, and the desktop check comes afterwards.