Why the app is built this way

Every real decision, and what's behind it.

There are two kinds of answer on this page, and you'll be told which one you're getting.

Some choices are backed by published research. Where they are, there's a link to the studies — including the ones that disagree with each other, because several of them do. The rest are my judgment. I have ADHD, I've packed badly for a long time, and some of this is simply what works.

An app that can cite a study for every button is telling you about its marketing, not its design.

The list starts full

A new trip arrives already populated. Your first act is deleting, not writing.

Starting is the expensive part. On the standard adult self-report measure, the scales for initiating a task and for planning and organizing are both meaningfully elevated in ADHD, and planning breakdown is one of the most consistent findings in the lab literature.

An empty list asks you to do the hard thing first. A full one asks you to do the easy thing — react to what's already in front of you. The research on starting has the studies, and what they do and don't establish.

The library is large on purpose. Recognizing something you'd have forgotten is easier than retrieving it from nothing — which is why the app would rather show you a passport you don't need than wait for you to think of one. The research on memory covers what's established here and what's still argued over.

Lists only show you what's relevant. Tag a trip as a beach holiday in summer and the ski section doesn't appear. The research on deciding covers how much of the choice-overload literature actually holds up — it's more contested than most apps citing it admit.

Eight sections are pre-ticked when you create a trip. The first screen shouldn't be a decision.

A trip has phases, not one endless list

Prep, Pack, Travel, Plans, Return — created automatically, four visible at once. A single list holding "book kennel", "pack socks" and "collect passport from the drawer by the door" is three different jobs wearing one coat. Planning breakdown is among the strongest findings in ADHD research, and the one adult study to take prospective memory apart found the problem concentrated in planning specifically rather than in remembering later.

The trip home is modeled as a second packing event, because it is one, and attention has usually left the building by then. Most apps treat the return as an afterthought, which is exactly backwards — and it's the part of travel I get wrong most often myself.

Any trip can be saved as a template, so the next similar trip starts from your defaults rather than mine. Executive-function differences persist into adulthood, which means a setup cost paid per trip is paid forever.

Nothing you do can break anything

Editing your library never changes a trip you've already made, and trips never write back to the library. The two are deliberately separate.

This is about fear rather than memory. If experimenting can wreck something, you stop experimenting — and an app you're afraid to poke at is an app you use at ten per cent.

No account, no sign-up, no analytics. Nothing to remember, nothing to lose, and no wall between you and the thing you opened the app to do.

The screen tries not to overwhelm you

Groups start collapsed. You expand what you're working on instead of meeting three hundred rows at once. The difference between a list you open and a list that makes you put the phone down is usually just how much of it arrives at the same moment.

A ticked item stays visible for a moment before it hides, so you can see the tick registered. Instant disappearance reads as a slip of the thumb.

The screen won't lock while you're packing. You're across the room with your hands full, and a locked phone is a re-entry cost. Re-entry is where sessions die.

Names are in sentence case — Check detailed weather forecast, not Check Detailed Weather Forecast. Proper nouns keep their capitals. Title Case gives every word the same weight, so nothing leads and your eye has no way in.

Some things matter more than others

Any item can be marked critical, and 31 are marked already. Medication and a passport are not the same kind of object as a spare shirt, and the app doesn't pretend otherwise.

A critical item replaces its checkbox with a red warning mark. The signal occupies the control you have to touch anyway, so it can't be skipped past, and the shape carries the meaning rather than the color doing all the work alone.

Double Check sits at the bottom of Travel, gathering every critical item, each with its own tick. Confirming at the door is a different act from packing at 11pm, and it gets its own moment.

That's the answer to the unpacking-to-check loop: one place, at the end, where you confirm instead of trying to remember.

The research behind any of this, with what each study actually measured, is on the evidence pages. How I know this explains how I decide what to claim.