One screen, no menus: why your parent's side of Marlow shows so little

Open the family side of Marlow and you get a schedule, a circle, a way to add things and a way to claim rides. Open your parent’s side and you get one screen. Today, what’s next, when to be ready, who’s coming. No tabs along the bottom, and nothing to go back from.

People sometimes assume the senior side is the family app with the hard parts taken out. It isn’t, and this post is about why. It’s the third in a series on the research behind the senior screen.

Every extra option costs time

The Hick Hyman law is one of the oldest results in the field: the more options a person is choosing between, the longer the choice takes. It holds for a row of buttons as much as for a grid of icons on a home screen. The effect shrinks with practice, which is why the remote you’ve used for ten years feels fine and the one in the hotel room doesn’t. A phone that arrives new, with an app nobody asked for on it, is the hotel remote.

For a younger user the cost is small and mostly invisible. For an older one it stacks on top of everything below.

What a mind can hold at once

Baddeley and Hitch described working memory as a small, active store where you keep the things you’re using right now: the name you just read, the step you were about to take. Miller’s famous “magical number seven” put a rough size on it, and Cowan later argued the real limit is closer to four items. Whichever number you prefer, it’s small. And working memory capacity declines with age.

In ordinary healthy aging that decline is gradual, and most people work around it without noticing. Where memory is genuinely going, they can’t, and that’s the parent this screen is built around.

An app with menus asks you to hold things in that store. Where am I. Where was I before this. What was on the other tab. Which of these four things is the one I wanted. Every screen transition is something to remember, and the person doing the remembering has less room than she used to.

One screen means there’s nothing to hold. What you need is in front of you, and it’s still there when you look back.

Slower, and worse at two things at once

Salthouse’s processing speed theory says that a general slowing of cognitive processing accounts for a lot of the difference between older and younger people on cognitive tasks. It isn’t that any one step fails. Each step takes a little longer, and an interface that needs ten steps compounds it.

Divided attention gets harder with age as well. Reading a screen while the kettle boils and somebody is talking in the next room is dual tasking, and older adults find it harder than younger ones do. A screen that needs you to keep track of where you are in it fails at exactly that moment, at 8:40 on a Tuesday with one arm in a coat.

Why a stripped down family app would still be wrong

Given all that, the obvious move is to take the family app and remove things until it’s simple enough. We didn’t, because a cut down tool is still a tool. It still has a place you are and places you aren’t. It still has a way to get lost.

The senior side was designed the other way round, starting from the one question your parent actually has: what’s happening, and when do I need to be ready. The answer to that is a display, not an app. There are no settings on her side, because the family sets everything from theirs. It never asks her a question, and it never needs a decision from her.

That costs something, and you should know what. The screen shows today and what’s coming next. It doesn’t show the month, and she can’t look up what’s on the 22nd or where the dentist is until it’s near. A parent who plans ahead and likes a paper calendar on the fridge should keep the paper calendar; this doesn’t replace it. And a parent who is perfectly good with a phone may not want a screen this quiet at all. Nothing stops a family from inviting her into the circle like anyone else.

The senior side page shows it next to the family side. The post on why that screen has no buttons covers what the decision rules out, and Big targets and no mistakes covers the other half of the argument, the one about hands and fear.

What she never sees

There’s a second reason for showing so little, and it’s not about memory. When a ride hasn’t been claimed yet, the family side says so plainly: this one still needs a driver, and the circle gets nudged as the date gets closer. That’s useful for the adults. It’s what gets the ride covered.

Your parent’s screen never shows it. If a ride is unclaimed, her screen says the ride is being arranged. That’s true, and it’s all she needs. The negotiation over who’s driving on the 22nd, the sibling who still hasn’t answered: none of it reaches her.

Partly that’s the attention argument again. A gap is a thing to worry about, and worry takes up the small store we’ve been describing. But mostly it’s a judgment call, and we made it on the side of kindness. A parent who can see her children working out who is least busy can start to feel like a burden, and a parent who feels like a burden can start canceling appointments. Solve it among the adults. Hand her the result.

Not every parent wants to be handed the result. Some would rather know the ride isn’t covered so they can call a neighbor or book a cab themselves. If yours is that parent, her screen won’t tell her, and you’ll need to, the way you always have.

What we can’t measure

We’ve read the research. We haven’t tested our screen against it, and we’re not going to pretend otherwise. Marlow runs no analytics, so we can’t see how long she looks at the screen or whether she ever hunts for a menu that isn’t there. We ask families instead, and Marlow is small enough that we can. If your parent finds the screen confusing, or wants something on it that isn’t there, write to us and say so. It’s the only way we find out.