Eleven claims, ten rivals, and the row we lose

Every cell in the table below is a checkable claim about a named product, checked against that product’s own public listing on a date we publish. Two of these cells were wrong when we first wrote them, and both were the kind of error that would have been published rather than caught, so the table is generated from one readable file and nothing here is a guess.

Last reviewed 1 October 2026

Which app blocker should you pick, in short

If you want study content in front of you when you open the app, Popcue is the only blocker here that asks a question drawn from material you already keep. It reads Notion, AnkiDroid or an LLM endpoint you run, live and uncapped, makes you answer before the app opens, and has no skip control. Every other blocker in the table makes you wait, exercise, breathe, answer a self-graded prompt, or pay. Four of them ask a question rather than making you wait: Hopopop, FocuzPass, Tok Blok and Study Lock, and all four draw that question from a bank they ship, not from anything you wrote. Hopopop is the nearest equivalent that exists, and the row that separates the two is the source of the card.

If you want a hard stop, Popcue is the wrong tool. Opal schedules hard blocks and has a Hard Mode its own site calls “no way out”. Freedom syncs a block across Mac, Windows, iOS, Android and Chromebook. One Sec and App Pause block websites. Popcue has no iOS version, does not block websites, and cannot lock itself shut.

And two free options deserve their own paragraph. AnkiDroid with AnkiBlock on top costs nothing, has 10M+ downloads, and gates your distracting apps on finishing your Anki cards. If that already works for you, nothing here is going to beat it. Popcue is for people who do not want to run a second study app.

The table

Read a tick as “this is documented to work”, a cross as “this cannot work”, and a dash as “partly, and here is exactly which part”. Every dash carries its reason in the notes underneath the table, and the reason is also in the cell itself as a tooltip for anyone on a desktop.

Swipe the table sideways to see every competitor

Feature comparison between Popcue and ten competing app blockers, verified 2026-10-01
Feature	Popcue	One Sec	Hopopop	Opal	ScreenZen	FocuzPass	App Pause	Study Lock	AnkiBlock	Tok Blok	LLLock
Wraps any app you choose	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Puts a question in front of you before you get in	Yes	Partly	Yes	No	Partly	Yes	No	Yes	Yes	Yes	Yes
The question comes from material you already keep	Yes	No	No	No	No	No	No	No	Yes	No	No
Works from a live tool, not an exported file	Yes	No	No	No	No	No	No	No	Yes	No	No
Interrupts at a per-launch ratio, not a daily quota	Yes	No	No	No	No	No	No	Yes	No	No	Yes
No skip control on either step	Yes	Partly	Partly	Partly	Partly	No	Yes	Partly	Partly	Yes	Yes
Spaced repetition scheduling	Yes	No	No	No	No	No	No	No	Partly	No	Partly
Usable free, with no subscription	Yes	Partly	Partly	Partly	Yes	Yes	Yes	Partly	Yes	Partly	Partly
Android	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	No	Yes
iOS	No	Yes	Yes	Yes	Yes	No	No	Yes	No	Yes	Yes
Blocks websites	No	Yes	No	No	No	No	Yes	No	No	No	No

What “partly” means, and where each claim was checked

One Sec: Puts a question in front of you before you get in: One Sec documents a Lengo vocabulary integration and a conversational reflection prompt, so it can add a study step. Neither asks you something drawn from your own notes.
ScreenZen: Puts a question in front of you before you get in: ScreenZen lets you write a custom prompt to answer before unlocking. That is a prompt gate rather than graded recall: there is no answer to get right.
One Sec: No skip control on either step: One Sec’s interventions are designed to be stepped through, but a reflection prompt is an activity rather than graded recall. There is no answer to get right and then rate.
Hopopop: No skip control on either step: Hopopop is the closest thing to Popcue in this category, and its questions are built in: mental arithmetic at three difficulty levels, general knowledge across ten-plus categories, and a geography map quiz. Its own support page documents the skip: you can skip after three attempts, you earn no XP for it, and the app stays blocked for the rest of that session. The gate is real and it is not graded recall of anything you wrote.
Opal: No skip control on either step: Opal has a Hard Mode its own site describes as "no way out, you can’t turn Opal off". That is stricter than Popcue, and it is worth knowing that is the trade you are making.
ScreenZen: No skip control on either step: ScreenZen documents a limited number of unlocks, so the gate holds. The prompt is self-graded, so nothing records whether you got it right.
Study Lock: No skip control on either step: Study Lock earns screen time back by answering correctly, so the gate is real. But it is a time debt, not a block. Get it wrong and you owe more time, which is a different mechanic from Popcue’s.
AnkiBlock: No skip control on either step: AnkiBlock offers a 60-second temporary unlock, up to three times a day. This is the clearest no-skip difference in the table, and AnkiBlock’s own listing documents the bypass plainly.
AnkiBlock: Spaced repetition scheduling: AnkiBlock schedules nothing itself. It delegates to AnkiDroid, so it inherits SM-2 from the deck you already keep.
LLLock: Spaced repetition scheduling: LLLock repeats words before you would forget them. It does not document which algorithm it uses.
One Sec: Usable free, with no subscription: One Sec blocks one app free and sells the rest. Its own pricing page returned a 404 at the date above, so no figure is quoted here.
Hopopop: Usable free, with no subscription: Hopopop documents a seven-day trial with no card needed, and no permanent free tier anywhere on its site. Its pricing is quoted in euros, and the figures differ between its own support page and its own store listing, so none are reproduced here.
Opal: Usable free, with no subscription: Opal allows one rule free. The rest is $99.99/year, $239/year, or $399 lifetime.
Study Lock: Usable free, with no subscription: Study Lock is free up to an allowance, then $34.99/year or $5.99/month.
Tok Blok: Usable free, with no subscription: Tok Blok has a free tier and a seven-day trial. The App Store lists monthly and yearly subscriptions plus coin packs, and its own blog quotes a different annual price than the store does, so neither figure is repeated here.
LLLock: Usable free, with no subscription: LLLock has in-app purchases. Its exact price was not verifiable at the date above.

Every capability claim above was checked on 2026-10-01 against the product’s own public listing: One Sec, Hopopop, Opal, ScreenZen, FocuzPass, App Pause, Study Lock, AnkiBlock, Tok Blok, LLLock. We are not affiliated with any of them. If something here is out of date, tell us and we will correct it and change the date.

Where another app is the better choice

A comparison that only argues one side is an advertisement. So, plainly: on several of these rows a competitor is simply the better tool, and in some cases the free one wins outright.

One Sec, if the problem is websites

One Sec blocks websites through a Safari extension on iOS, which Popcue cannot do at all. It also has more than a million Google Play downloads, around 46,000 reviews, and a granted US patent. If your time is going in the browser rather than into an app, read the head-to-head page.

Opal, if you want a hard lockdown

Opal schedules hard blocks on a timetable, runs on iPhone, iPad, Mac and Android, and has a Hard Mode its own site calls “no way out”. It also claims a 4.8 rating with more than 150,000 app ratings and an Apple Design Award. See the head-to-head page.

Freedom, if you use more than your phone

Freedom syncs a block across Mac, Windows, iOS, Android and Chromebook, and a block that follows you off the phone is worth more than one that does not. See the head-to-head page.

AnkiDroid and AnkiBlock, if you already study with Anki

AnkiDroid is free, open source, has 10M+ downloads and about 165,000 reviews, and AnkiBlock adds the app gate on top of it for free. If that habit already exists, do not pay for anything. See the head-to-head page.

Hopopop, if a general-knowledge quiz is what you actually want

Hopopop is the closest thing to Popcue in this category, and it is better at the one thing Popcue cannot do: it works on iPhone and iPad as well as Android. Its questions are built in, mental arithmetic and general knowledge and geography, and its own support page offers a skip after three attempts. If your interest is “make opening the app cost me a brain cell”, Hopopop does that today and Popcue is a later, narrower thing.

App Pause, if the answer is websites or a tablet

App Pause blocks websites in Chrome, Firefox, Brave and DuckDuckGo, covers Android tablets, and shows you your own usage data when it pauses an app. Its core features are free with no subscription, and its paid tier is Pause+. It asks no question, so it is not a substitute for what Popcue does, but on two of its rows it is simply ahead.

ScreenZen, if free is the whole point

ScreenZen is usable free with no subscription, which is the same tick Popcue gets, and it is a reasonable app blocker. It asks you a self-graded custom prompt rather than a question with a right answer.

LLLock, if what you are learning is words

LLLock is built for one job: vocabulary, across 30+ languages and offline. If that job is yours, a focused tool beats a general one, and the question Popcue asks comes out of your notes rather than out of a language course.

When these claims were checked: 30 September 2026. Every cell above was read off the product’s own public listing on that date, which is why the date is on the page rather than in a changelog. Competitors ship. A rival adds a study step, another adds a bypass, a third changes platform, and an undated claim about somebody else’s product is a bet rather than a statement. If you find a cell that has gone stale, tell us which one and we will correct it and move the date.

Five competitors, five longer pages

Each of these takes one rival and gives it a full page, including the section where that rival is the better choice. They are longer than this page on purpose: a comparison that only runs the argument in one direction is not worth reading twice.

Popcue vs One Sec Friction against recall, plus the patent, the install count and the Safari extension One Sec has and Popcue does not. Popcue vs Hopopop The nearest equivalent that exists: same mechanic, built-in questions, an iPhone app, and a skip after three attempts. Popcue vs Opal A page that starts by saying Opal is the better blocker, and then explains when the card is the part you want. Popcue vs Forest and Freedom Timers and schedules, cross-device sync, and an honest note on the half of this comparison we could not verify. Popcue vs Anki and AnkiBlock A free, open-source, 10M-download answer to “do I need two apps?”, and the one case where the honest answer is to keep Anki.

What Popcue does not do

The row where Popcue says no is in the table rather than in a footnote, and it is not the only one:

Popcue does not block websites. It is the first column and the last row, and it is a cross. One Sec blocks sites through a Safari extension; browser blocking on Popcue is on the roadmap and is not shipped.
There is no iOS version and none is scheduled. One Sec, Opal, ScreenZen, Study Lock and LLLock all have one. We would rather ship one platform properly than hint at a date we cannot stand behind.
Popcue cannot lock itself shut. There is no Hard Mode, no password and no way for Popcue to refuse to be turned off. If you need a door that does not open from the inside, Opal is built for that and Popcue deliberately is not.
Popcue has no desktop app and nothing syncs across your devices. Freedom blocks on five platforms at once. Popcue runs on Android and web, on one device.
Popcue has no public install count, rating or review, because it is not on the Play Store yet. A competitor with a million downloads has a decade of other people’s bug reports that we do not have.

How the interrupt works, in four movements, including the parts that are a design position rather than a research finding.

Two design questions the table cannot answer

Some of what separates these apps is not a capability but a decision, and a table is the wrong place for a decision. Both of these are written up in full, including the parts that argue against us.

Why five in ten beats every launch Per-launch ratio against a daily budget, why the five are randomized, and what a missed interrupt costs. Spaced repetition without a study session Why review belongs on an interruption you were already going to cause, and where that is the wrong tool.

Where to go next

How Popcue works The per-launch ratio, the two taps, the eight card types and what SM-2 does without the jargon. Notion, AnkiDroid, your own LLM How each connector works, and exactly what leaves your device. Frequently asked questions Permissions, iOS, the skip button, and getting your phone back.