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Attention, friction, and hardware.
This is the essay layer of the site: dated arguments about why Spark is shaped the way it is — the design decisions, the engineering trade-offs, and the limits we decided not to paper over.
How-to8 min read
Why you can't read a book any more, and what actually fixes it
It isn't your attention span. It's that the book has to win an argument with a device engineered to win arguments — every few minutes, for an hour.
Everything else
Newest first. Each one stands on its own — there is no reading order and no series to catch up on.
The best app blockers in India, honestly compared
What you can actually buy in India, what each costs in rupees, and which ones ship here. Free tools first, then the apps, then the physical keys.
12 min readBuying guide · 23 Sept 2026The best app blockers in 2026, ranked by how hard they are to bypass
One ranking axis: what it takes to get back in. Physical keys, software strict modes and gentle nudges, with what each actually enforces.
11 min readComparison · 23 Sept 2026Blok vs Spark: the card, the subscription and the price over three years
Blok pairs a $29 NFC card with a paid app. Spark is a one-time key with a free app. What each enforces, and what each costs by year three.
7 min readComparison · 23 Sept 2026Detach vs Spark: two physical blockers, $9.99 and ₹999
Detach is a free iPhone and Android app with a $9.99 NFC card. Spark is a key priced in rupees. Where each one is genuinely the better buy.
7 min readComparison · 23 Sept 2026Bloom vs Spark: a $39 steel card against a ₹999 key
Bloom is a well-reviewed NFC card with no subscription. Spark is a key priced in rupees. The real differences are stock, shipping and the unlock.
7 min readComparison · 23 Sept 2026The $9 Autonomous Key vs Spark: what nine dollars buys
The Autonomous Key is the cheapest NFC key sold. It opens a 60-minute window on each tap, which is a different mechanism from a session you must end.
6 min readComparison · 23 Sept 2026TapBlok vs Spark: the free Android route, and where it stops
TapBlok is free, open source and turns any NFC tag into an app lock on Android. What you give up by not paying, and when that matters.
7 min readComparison · 23 Sept 2026Forest vs Spark: a tree that dies, or a key you fetch
Forest is a focus timer with a Give Up button. Spark is a lock with a physical unlock. They solve different halves of the same problem.
6 min readComparison · 23 Sept 2026Lockdown vs Spark: no early exit, or no switch on the phone
Lockdown holds an iPhone block until the timer ends, for $24.99 a year. Spark moves the unlock off the phone for one payment. When each is right.
6 min readHow-to · 23 Sept 2026How to block Instagram, and make it stick
Every method on iPhone and Android, in the order worth trying: the free ones first, then what to do when you keep lifting your own limit.
8 min readBuying guide · 23 Sept 2026Physical app blockers in India: what reaches you, and what it costs
Every physical blocker you can get in India, with rupee prices, import reality and shipping times — and the free NFC-tag route that costs nothing.
10 min readDesign · 8 Jul 2026Locking and unlocking should not cost the same
A blocker that costs as much to switch off as to switch on gives the final say to your most tired self. Why Spark makes locking free and unlocking a walk.
6 min readProduct · 17 Jun 2026Why a focus tool shouldn't be a subscription
A subscription pays its maker for as long as you still need it. Why Spark is a free app and a key bought once, and what that key can and cannot enforce.
5 min readEngineering · 20 May 2026How the first Spark unlock worked
The first Spark answered a random challenge with an HMAC-SHA256 response. Neither key sold today does: the original design, and what the key checks now.
7 min readEngineering · 29 Apr 2026Why we replaced the NFC tag with a Bluetooth key
Why the first Spark moved from an NFC tag to a Bluetooth key, what we thought we were giving up — and what has changed since.
6 min readIf you came for instructions
- Guides — the maintained how-to layer, covering every blocking method on both platforms, including the ones we do not sell.
- How it works — what the tap actually does, what unlocking takes, and why locking still works with Bluetooth switched off.
- Comparisons — Spark set against the software blockers and the other physical devices, with the cases where they are the better answer left in.
- Pricing — what each key costs, what arrives in the box, and why there is no subscription to cancel.
The argument only matters if you try it.
Everything above is theory until the key is in another room. Once it is paired, locking is one tap and works with Bluetooth off. Unlocking is the part that asks you to stand up — and hold your phone against the key.