What Apple's Screen Time will and won't let an app do

Every app blocker on the App Store is built on the same Apple frameworks: Screen Time, Family Controls and Device Activity. That's what makes the blocking real. iOS does the shielding, so it holds when the app that set it is closed.

It also means every one of these apps inherits the same constraints. They aren't bugs, and no amount of engineering removes them. An app can only be honest about them or quiet about them.

Here's the full list, and what each one costs you.

An app never learns which apps you blocked

When you choose apps in the Screen Time picker, iOS doesn't hand the app a list of names. It hands back an opaque token: a sealed reference that can be passed back to iOS to say "shield this", and can't be opened to read what it points at.

So a block shows a count and Apple-rendered icons instead of a list of names. It reads as a missing feature, and it's the strongest privacy guarantee in the whole category. An app built this way can't know which apps you struggle with, because the system never says.

The same design is why no app can offer to search your apps by name, or tell you which app a shield belongs to when one appears.

Nothing syncs between devices

Those tokens are issued per device. A token minted on one device means nothing on another.

This is worth being precise about, because it's stronger than "this app has no sync feature". Even if an app added a full sync backend tomorrow, it couldn't carry your app selections across. You'd still choose your apps again on the second device.

An app may only hold 20 active monitors

iOS caps how many Device Activity monitors a single app can register at once, and that ceiling is 20. It isn't a pricing decision anybody made. It's the number the system enforces.

That's worth watching for when you compare apps. An app advertising "unlimited" blocks is either counting something other than concurrent monitors, or letting the twenty-first fail to arm. A block that doesn't enforce is worse than no block, because you plan your day around it.

Location blocking needs "Always", and iOS asks twice

A block that switches on when you arrive somewhere has to run while your phone is in your pocket and the app is closed. iOS only wakes an app for a geofence crossing if it holds "Always" location with precise accuracy. With "While Using", the block only changes state while the app is open on screen, which is exactly when you don't need it.

iOS also won't offer "Always" up front. The first prompt offers only "While Using". The next time you arrive at one of your places, iOS asks whether to upgrade, and that second prompt is the one that matters. It's a privacy protection, and it means a location block can look broken for a day before it starts working.

64 scheduled notifications, across everything

An app may have only 64 notifications scheduled at a time. A handful of daily routines with several reminder times each reaches that ceiling faster than you'd guess.

What happens at the limit is up to the app. iOS itself just drops whatever doesn't fit. An app that budgets its slots can protect the notifications that matter, like a routine starting or a warning that a block has stopped enforcing, and trim repeat nudges first.

Screen Time access can be switched off at any time

It's a permission like any other, and revoking it stops all blocking instantly and completely. Without it there's nothing to enforce any rule.

The failure mode to care about isn't the stopping. It's not being told. If you think you're still protected, you stop checking.

Some devices can't grant it at all

A device managed by an employer or a school, some child accounts under Family Sharing, and devices where Screen Time has been restricted can't grant the permission. Where the device is managed, the restriction belongs to whoever manages it, and no app can ask its way around it.

The usage report is sealed

Your Screen Time usage report is drawn by Apple, inside a separate view that an app can place on screen but can't read, copy, screenshot, or export.

That's a good design. It lets an app show you your own usage without ever being able to send it anywhere. The trade-offs are real, though: a few seconds of loading while that separate view starts, and no way for the app to use those numbers in anything else it calculates.

Any app can be deleted

No app on iPhone or iPad can prevent its own deletion, and deleting an app removes its blocks with it. Any product implying otherwise is overpromising.

This is the one that changes what these apps are for. They're tools for someone who wants to spend less time on their phone, not locks to impose on someone who doesn't. If you want restrictions that survive a determined moment, Apple's own Screen Time passcode is the right tool, and it works alongside a blocking app, not instead of one.

Why Motiv publishes this

Every app in this category lives with the list above. We'd rather you meet it here, calmly, than discover it one item at a time and conclude the app is broken.

It also sets a fair test for comparing any of them, Motiv included: an app can't be judged on whether it has these limits, only on whether it tells you about them and handles them well. A 20-block cap shown honestly and an "unlimited" claim that silently fails are the same constraint, handled two different ways.

Motiv's FAQ answers these one at a time, and how Motiv works covers what it does inside them. If you want the mechanism rather than the constraints, how app blocking actually works on iPhone and iPad starts one step further back.