Why your screen turns off while you're cooking

What is actually happening

It is a setting called Auto-Lock, and it lives in Settings, Display & Brightness. By default an iPhone dims and then locks the screen after thirty seconds to two minutes of no touches.

Reading does not count as a touch. Neither does standing over a pan. As far as iOS is concerned you walked away, so it does the sensible thing and locks the phone to save battery and to stop a stranger reading your messages.

The fix everyone tries

Settings, Display & Brightness, Auto-Lock, Never. It works, and there are three reasons not to do it.

• You will forget to put it back. That is the real cost. The phone then sits at full brightness in your pocket, in your bag, on a table, for the rest of the week.
• Battery. The display is the single biggest consumer of power on the phone, by a distance.
• Your phone is unlocked on a counter, indefinitely, in a room other people walk through.

It is a global switch being used to solve a local problem, which is nearly always the wrong shape of fix.

What a wake lock does instead

A wake lock is a request an app makes that says: while this specific screen is open, do not sleep. The moment you leave, the request is released and Auto-Lock goes back to whatever you had it set to. You never touch Settings and there is nothing to remember to undo.

This is a normal capability. It is what maps apps use for turn-by-turn directions and what music apps use in a car. There is nothing exotic about applying it to a recipe.

What that looks like while you cook

Sift calls it Cook Mode. It holds a wake lock for exactly as long as you are in the recipe, and it re-takes the lock if you leave the app and come back, which is the part that usually breaks. Alongside it:

• Type set large enough to read from across the counter.
• Steps you tap off as you pass them, so you can find your place after a distraction.
• Timers read out of the step text, so "smoke for sixteen hours" becomes a timer you start with one tap. It fires with the app closed.

Leave the recipe and your phone goes back to locking on its own schedule.

A note on greasy hands

The reason this matters more than it sounds is that the moment the screen goes dark is almost always the moment your hands are covered in something. Waking the phone means finding a knuckle, or a wrist, or washing and drying your hands for the fourth time. Thirty seconds is not very long when you are chopping.

Does this work on Android

Android has the same concept and the equivalent setting is Screen timeout. Sift is iOS for now, and app.siftapp.me opens in any browser, where Cook Mode uses the browser's own Screen Wake Lock API.