One Sec adds friction. Popcue adds a question.

One Sec is a serious piece of software: more than a million installs, a granted patent, a Safari extension and years of people using it. This page is not an attack on it. It is an attempt to be precise about the one thing the two products do differently, and to say plainly where One Sec wins.

Last reviewed 1 October 2026

Popcue vs One Sec, in short

One Sec adds friction: a pause, an exercise or a short block before the app opens, and it cannot show you a question from material you already keep. Popcue replaces the pause with a two-tap forced recall drawn from your own connected notes, and there is no skip control on either tap. That is the whole difference, and it is worth saying out loud: One Sec makes you wait, Popcue makes you retrieve something, and retrieval is what makes it stick.

One Sec also has four things Popcue does not and will not have. It blocks websites, through a Safari extension on iOS. It holds a granted US patent. It has more than a million Google Play downloads and around 46,000 reviews behind it. And it has a Lengo vocabulary integration, which puts a real study step in front of you if the thing you are learning is words. Popcue has none of those, has no iOS version, and has no public install count at all.

One Sec’s price could not be verified. Its own pricing page returned a 404 when we checked on 30 September 2026, so there is no figure anywhere on this page, and no comparison of what each one costs.

The short table

Ten rows, pulled from the full matrix on the comparison page, and only the ones where the two products differ. A dash means partly, and the reason is under the table.

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 One Sec is better

This section is not a formality. On the points below, One Sec is the better product and the honest thing to say so plainly.

It blocks websites, including in Safari on iOS. Popcue does not block websites at all, and with no iOS version it cannot block them in a browser either. If your problem is a browser rather than an app, One Sec is currently the right tool and this page is not going to pretend otherwise.
It holds a granted US patent. Popcue has no patent and is not going to claim one. Whatever that is worth to you, it is real and it is not ours.
It has more than a million Google Play downloads and around 46,000 reviews. That is years of other people hitting the edge cases first. Popcue is not on the Play Store, so it has no public install count, no ratings and no reviews at all.
It has a Lengo vocabulary integration. If the thing you are studying is vocabulary, One Sec can put a study step in front of you from a curated language source. Popcue’s cards come from your own tools, so if Lengo is where your material lives, you cannot point Popcue at it.
It has an iOS app. If your phone is an iPhone, Popcue is not available to you today, full stop. That is not a comparison point; it is a fact about your phone.

And one thing we could not check: One Sec’s price. Its own pricing page returned a 404 on 30 September 2026, so there is no figure here and no claim about which is cheaper. Check it yourself before deciding on cost.

Where Popcue is better

The same number of points, argued just as carefully.

The question comes from material you already keep. Notion, AnkiDroid, or any MCP-compatible LLM endpoint you already run. One Sec’s study step is either its own reflection prompt or a Lengo vocabulary item; nothing in its documentation takes your own notes as the source of the question.
It works from a live tool, not an export. Connect a Notion page once and the cards change when your notes change, with no re-import and no second copy of your material living in somebody else’s silo.
It interrupts at a ratio of launches, not a daily budget. Five out of ten by default, randomized within the ratio, set per app, with active hours so it never fires at 1am. One Sec’s interventions depend on which ones you have switched on, not on how often you open anything.
Recall is graded, and the grade schedules the next card. Two taps: reveal, then rate Got it or Still learning. The second tap updates an SM-2 scheduler, so a card you keep missing comes back sooner and one you keep getting right comes back later. A pause has nothing to record.
It is free from your own tools, permanently, uncapped. Notion, AnkiDroid and your own LLM cost you nothing on any tier, with no cap on how many you connect. Five active AI-written paths are free too, and Pro is ₹149 a month or ₹999 a year if you want more of them.
Two Android permissions, and nothing is read from inside the apps. Usage access, so it knows an app you picked just opened, and draw over other apps, so the card is what is on screen. It does not use the AccessibilityService API, and it has no public ratings because it has never been downloadable by anyone but us.

Who should pick which

Pick One Sec if: You are on an iPhone, or your distraction is a website rather than an app, or you want the version of this that a million people have already put through its paces, or the material you are studying is vocabulary and Lengo is where you keep it.
Pick Popcue if: Your notes already live in Notion, AnkiDroid or an LLM you run, and the thing you want is to be asked something from them at the moment you reach for the feed. If you have never been quizzed at the point of temptation before, that is the difference this makes.
Pick either, and notice this: A blocker works by being annoying. Both of these are annoying, on purpose, and a person in a bad moment will resent both. Popcue’s answer to that is a lower ratio, active hours, or turning it off from Settings with no fee. Neither product is a substitute for anything a clinician would advise, and neither makes a health claim.

Where this came from

Two sources, both read on 30 September 2026: one-sec.app and One Sec’s Google Play listing. Everything we could not read there is not on this page. Popcue is not affiliated with One Sec, and if you own it and something here is wrong, tell us and we will change it and move the date.

Three questions

Is One Sec better than Popcue?

Not on the thing Popcue is for, and yes on several things it is not. One Sec is better made, holds a granted US patent, has more than a million Google Play downloads and roughly 46,000 reviews, and blocks websites on iOS through a Safari extension.

Popcue is better at one specific thing: it asks you a question from material you already keep and makes you answer it before the app opens. One Sec’s interventions add friction. Popcue’s add recall.

Does One Sec block websites, and does Popcue?

One Sec does, through a Safari extension on iOS. Popcue does not, and it has no iOS version at all, so it cannot block sites in Safari either. Website blocking is on Popcue’s roadmap and is not shipped.

If stopping websites is the problem you are solving, One Sec is the right tool today.

How much does One Sec cost?

We could not verify it. One Sec’s own pricing page returned a 404 when we checked on 30 September 2026, so there is no figure on this page. What One Sec documents is that one app is blocked free and the rest are sold.

Popcue is free forever for anyone whose cards come from Notion, AnkiDroid or their own LLM, with no cap on how many they connect, and Pro is ₹149 a month or ₹999 a year.

Where to go next

The full comparison Eleven rows, ten rivals, and the row where Popcue says no. 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. How Popcue works The per-launch ratio, the two taps, and why there is no skip button. Frequently asked questions Permissions, iOS, the skip button, and getting your phone back.