Named after
a slow tree.
Tilia is the linden. It takes decades to fill out and then stands for centuries — which is roughly how a vocabulary works, and nothing at all like how vocabulary apps usually behave.
The problem is not that people don’t read
Serious readers meet unfamiliar words constantly. Most of those words are lost within the hour: you infer enough from context to keep going, the page turns, and that’s the end of it. The habit that would fix it — stop, look it up, write it down, review it later — is so tedious that almost nobody sustains it, and the people who do end up maintaining a word list instead of reading.
Meanwhile, the apps built for vocabulary teach from someone else’s list: decks of words chosen for an exam, in sentences written by nobody, disconnected from anything you care about. They work in the way flashcards always work, and they are dull in the way homework is dull.
So Tilia does the tedious part
Give it a book and it reads the whole thing first: every word looked up against a full English dictionary, inflections resolved back to their headword, and then filtered against how large your vocabulary already is. What survives that filter is a deck of words that are genuinely new to you, each one carrying the sentence you were about to read it in.
That single idea decides most of the product. It’s why the vocabulary test exists (the filter needs to know your level, and guessing would make the whole thing noise). It’s why cards are attached to books rather than to categories. It’s why the review schedule is spaced repetition rather than a daily quota — the goal is to stop showing you a word, not to keep you in the app.
And the reading stays social
Reading the same book at the same time as someone else is one of the oldest pleasures there is, and it survives badly on modern phones. Co-reads are Tilia’s answer: one book, a finish date, a few people, shared highlights you can argue under. Everyone builds their own vocabulary from the same pages, because everyone starts from a different level.
Who makes it
Tilia is independent and small — no ad network, no data brokerage, and no growth team inventing reasons to send you a notification. It’s paid for directly by the people who subscribe, which is the whole reason the free plan can stay genuinely useful instead of being a demo.
If something is broken, missing, or annoying, writing to us actually reaches the person who can change it: newtonianianlabs@gmail.com.