Phone or Laptop? Which Assessments Survive a Small Screen

The internet answer to this question is "use a laptop", which is right often enough to be useless. Some assessments will not open on a phone at all, some are built for one, and the rest sit in between. Publishers put more in writing about this than candidates realise, so what follows comes from their candidate guidance.

What the providers actually say

One more worth knowing. SHL publishes whether the assessments you were sent are mobile enabled on your assessment home page, so the answer is per assignment rather than per vendor. That is the pattern across the industry: several other publishers set the position per assessment rather than per company, which is why no general rule about a provider is worth as much as the line in your own invitation.

Why data interpretation punishes a small screen

The cost of a phone on a numerical item is not that the numbers are too small to read. It is that the question, the table and the options cannot be on screen together, so every item becomes a sequence of scrolls with a memory reload at each one. Across a full SHL Verify style numerical section that is not marginal. Three failure modes do most of it:

• Wide tables become nested scrolling.A table that does not fit gets a horizontal scroll inside the page's vertical scroll, so a drag you meant as page movement moves the table instead and you lose your column.
• Charts lose their labels first. Axis ticks, legends and inline data labels shrink first when a chart is squeezed, and pinch zoom is often disabled on assessment pages.
• Tabbed source documents multiply it. Formats that split data across tabs, as the Aon scales tests do, are partly a test of how fast you locate a figure, so extra scroll distance attacks the skill being measured.

Abstract reasoning is worse, not better

Abstract items look like they should survive a phone because they are pictures rather than text. They survive least well of anything. The discriminating feature in a matrix item is routinely one small detail: an extra dot, a shading direction, a slightly thicker line, a shape rotated a quarter turn rather than a half. Legible at laptop size, genuinely ambiguous once the grid is scaled to phone width and the options reduced to thumbnails beneath it.

The second problem is comparison. Solving one of the standard pattern families, or tracing rules through a diagrammatic item, means holding what you inferred against each option. Below the fold, you are comparing against memory.

Touch against mouse on timed reaction tasks

This is more interesting than the usual claim that touch is slower. It is not: a tap is direct pointing with no cursor travel, so on large, well-spaced targets a thumb beats a mouse. What costs you is everything around the tap.

There is also a scoring question nobody answers: a reaction game compares your times against a norm group, and you cannot know what devices that group used. Do not assume the platform corrects for your hardware.

The exception is real, though. Criteria's mobile-first assessment and a game battery shipped as an iPhone app are designed around a thumb rather than adapted to one, and where a provider ships a candidate app for its games, as HireVue does, that app exists because the phone browser version was weaker.

Two phone browser traps, from building games for them

The worst mobile assessment problems are about the phone browser rather than the test, and they are invisible until you hit one under a clock. The first is the disappearing button. A phone browser reports a viewport height that assumes its own address bar is hidden, so a screen built to fill that height is taller than what you can see: the bottom strip, exactly where Start, Next and Submit live, ends up under the URL bar, and because the page believes it already fits there is nothing to scroll. Our own game screens are sized against the visible area rather than that reported height precisely so this cannot happen. The second is a centred screen on a short viewport, which overflows in both directions at once, heading cut off the top and button cut off the bottom.

The connection drop, and what happens to your attempt

Phones are the worst case, and not mainly because mobile data is unreliable. The risks are specific: handover from WiFi to cellular as you move, an incoming call backgrounding the browser, low power mode throttling the page, and the operating system discarding a backgrounded tab to reclaim memory. Several look identical to a dropped connection from the platform's side.

What happens next turns on whether the clock keeps running while you are away, whether answers were committed item by item or only on submit, and whether the session can be re-entered without an employer reset. SHL's published guidance shows the shape this takes: it tells candidates not to click the test's Exit button when a session freezes, because that can submit the responses entered so far, and to refresh or close the frozen window and use the Continue Assessment link behind it. Mechanics vary, but the lesson generalises: the action that destroys an attempt is usually the one taken in a panic.

The recommendation, by test type

If the phone genuinely is your only option

Ask first. If the assessment is one a phone handles badly, tell the recruiter before the deadline that you do not have laptop access and ask for an extension or an alternative. It is routine in high-volume recruitment, answered more often than candidates expect, and a different request from a formal adjustment.

Then remove every variable you control: the largest phone you can borrow, landscape orientation for tables and wide images, brightness up, low power mode off, notifications off, device on charge, and a practice run on the same handset. One full-length section on the device you will actually use tells you more in twenty minutes than any article can, which is why the week-before plan puts format rehearsal ahead of content revision.