Reference
What iPhone widgets can and cannot do
Widgets are more limited than they look, and the limits are deliberate. Here is what fits in each slot, what each iOS version added, and the things no widget will ever do.
Most frustration with iPhone widgets comes from expecting them to behave like miniature apps. They do not. A widget is closer to a printed card that the system reprints occasionally, and almost every quirk follows from that.
This page collects the practical constraints in one place: the slots and what fits in them, which iOS release added what, and the hard limits worth knowing before you go looking for a widget that does something widgets cannot do.
The slots, and what fits in each
There are six places a widget can go, three on the lock screen and three on the home screen. The lock screen slots are small by design, because they share space with the clock.
| Slot | Where it sits | Realistically holds | Since |
|---|---|---|---|
| Lock screen, inline | The line above the clock | A single short line of text, with an optional small glyph | iOS 16 |
| Lock screen, circular | Under the clock | A glyph, a very short value, or a small gauge | iOS 16 |
| Lock screen, rectangular | Under the clock, taking two circular slots | Two or three short lines of text | iOS 16 |
| Home screen, small | A 2×2 block of app icons | A headline value and a line of supporting text | iOS 14 |
| Home screen, medium | A 4×2 block | A few lines, or a short list | iOS 14 |
| Home screen, large | A 4×4 block | A paragraph, or a list of several rows | iOS 14 |
Exact pixel dimensions vary by iPhone model and by the text size set in Display settings, so "holds" here is what fits comfortably rather than a fixed character count. iPad adds an extra-large home screen size that iPhone does not have.
What each iOS version added
Widget capability has arrived in stages, which matters when an app says it needs a particular version. The current release at the time of writing is iOS 26.
| Capability | Introduced |
|---|---|
| Home screen widgets | iOS 14 |
| Lock screen widgets | iOS 16 |
| Interactive widgets (buttons and toggles) | iOS 17 |
| StandBy, the landscape charging display | iOS 17 |
| Widget tinting and free placement on the home screen | iOS 18 |
| Controls in Control Center and on the Lock Screen | iOS 18 |
Why widgets do not update live
This is the single most misunderstood thing about widgets, and the source of most one-star reviews. A widget does not run continuously and cannot fetch something the moment you look at it.
Instead the app hands iOS a timeline: a set of entries, each with a time it should be displayed. iOS renders those on its own schedule, and it rations how often an app is allowed to supply new ones. Apple does not publish a fixed number of daily refreshes, and the allowance varies with how much you use the app.
The practical consequences: opening the app tends to prompt a refresh, removing and re-adding a widget forces a clean start, and a widget for an app you never open will update least of all.
Things no widget can do
These are platform limits rather than gaps any developer can fill, so an app promising one of them is worth treating sceptically.
- Scroll. Whatever fits is what you get. There is no scrolling within a widget.
- Accept typed input. No text fields, no search boxes. Since iOS 17 a widget can hold buttons and toggles, and that is the extent of interaction.
- Play audio or video. Media app widgets show controls that command the app; the widget itself stays silent.
- Animate freely. Transitions between entries are limited and system-controlled. Nothing continuous, no video loops, no live counters ticking upward.
- Respond instantly to the outside world. A widget cannot poll a server when you glance at it. Anything it shows was prepared in advance.
- Run heavy work. Widget extensions are given tight memory and time budgets, so anything expensive has to happen in the app and be handed over ready-made.
What this means for learning apps
Read the list above and the shape of a good widget becomes fairly clear. Anything needing interaction, immediacy, or more than a few lines belongs in the app. What widgets are genuinely good at is putting a small, prepared piece of content somewhere you already look.
Vocabulary happens to fit that shape unusually well. A word, a translation, and a line of context need no interaction and do not go stale, and the thing that makes vocabulary stick is repeated exposure rather than concentration — which we went into in why you forget vocabulary.
It also sets the honest limit. A widget cannot quiz you, because it cannot take an answer. It can keep material in front of you; it cannot test whether you have learned it. That is the boundary Glancealot works within: it rotates a list you choose across your lock and home screen, and it pairs with something that asks you to produce the words rather than replacing it.
If you are comparing the apps that do this, we looked at the options in apps that put vocabulary on your lock screen.
A note on accuracy
Widget behaviour changes between iOS releases. Everything here was checked in August 2026 against iOS 26. Version numbers refer to when a capability first appeared, not when it last changed, and refresh behaviour in particular is described by Apple in general terms rather than fixed figures — treat any specific number you see quoted elsewhere with caution.
Frequently asked questions
A widget is not a running app. The app supplies iOS with a timeline of entries in advance, and iOS decides when to show the next one, budgeting refreshes across the day to protect battery. Apple does not publish a fixed refresh allowance, and in practice apps you open often are refreshed more generously than ones you rarely touch.
The home screen offers small (a 2×2 block of icons), medium (4×2) and large (4×4). The lock screen offers an inline slot on the line above the clock, plus circular and rectangular slots beneath it, where a rectangular widget occupies the space of two circular ones.
Since iOS 17 a widget can contain buttons and toggles, so it can perform simple actions like ticking off a task without opening the app. That is the full extent of it. Widgets cannot scroll, accept typed input, or respond to gestures beyond taps on those controls.
No. Widgets render static views and cannot play sound or video, which is why a media app widget shows playback controls rather than the media itself. Animation is very limited, so widgets are best thought of as a periodically redrawn image rather than a live surface.
The area under the clock holds up to four circular widgets, or two rectangular ones, or a mix, since a rectangular widget takes the space of two circular slots. The inline slot above the clock is separate and holds one.
Not significantly. The refresh budgeting that makes widgets feel slow to update exists precisely to limit their energy cost. Between refreshes a widget is a static rendering and consumes essentially nothing.
Yes, within limits. An app can build a timeline of entries with scheduled display times, so content can change through the day without the app running. What it cannot do is react instantly to something that happens outside that schedule.
