Routine Genius

Private AI apps that run on your phone, not in the cloud.
Language Cipher — speak badly in private, so you can speak well in public.

[Routine Genius @routine_genius]

@kenchung we bundle a 2.59 GB model inside the binary — 2.67 GB on the store, review passed it without a question. the thing that bit us: expo's FileSystem.getInfoAsync reads a whole file to stat it, 3×/boot on 2.59 GB ≈ 5 GB ≈ jetsam kill. native inode stat instead.

[Routine Genius @routine_genius]

Most streaks measure whether you opened an app.

The one in Language Cipher only moves on a day you finished a mission — a conversation, out loud, graded. Opening the app does not move it.

A streak should be a record of speaking.

https://t.co/VQqOb6eUnN

[Routine Genius @routine_genius]

@vibecodeapp @vishal_dubey the local version of this is shippable today: 2.59 GB of weights inside the binary, 15–25 s per reply on a phone CPU, and App Store review passed a 2.67 GB download. no streaming, no key, no bill.

[Routine Genius @routine_genius]

@MelissaEnchant @duolingo where it runs matters here: Max's roleplay and video call are GPT-4, per Duolingo's own blog. i ship the on-device version of that — 15–25 s per reply on a phone CPU, and it never reaches us. that's the whole tradeoff.

[Routine Genius @routine_genius]

@tchchia @XFreeze shipped one of these. the drill mattered less than the trigger — ours fires after three struggles and holds ~85% success. and if the model runs on the phone, budget 15–25s per reply; that pacing decides the whole feel.

[Routine Genius @routine_genius]

@100rabhAi if you're doing on-device STT: iOS 26's SpeechTranscriber matched faster-whisper on our labelled 10 — within 1% on word count — at 0 MB bundled, ~60x realtime. one catch: both engines confabulate on non-speech audio, so gate it.

[Routine Genius @routine_genius]

You already know which sentence you keep getting wrong. Nothing has ever stopped you saying it.

Miss a pattern three times in a mission and Language Cipher pulls you out, drills that one pattern, then puts you back in the scene.

$9.99 once. https://t.co/VQqOb6fsdl

[Routine Genius @routine_genius]

9/ Language Cipher — the app this came out of. On-device tutor, 6 languages, no account, no subscription, $9.99 once. iOS 15.1+.

https://t.co/VQqOb6fsdl

[Routine Genius @routine_genius]

1/ Notes from putting a 2.59 GB model inside an iOS app that's now on the App Store. Most of what I had to learn wasn't about the model — it was about Apple's packaging rules, which almost nobody writes about because almost nobody hits them.

[Routine Genius @routine_genius]

8/ Uploads get slow, by the way: every TestFlight and App Store build carries the full model, about 11 minutes of upload where it used to be seconds. Version bumps that don't change the model ship as deltas, so users aren't re-downloading 2.66 GB for a bug fix.

[Routine Genius @routine_genius]

And no server means I can't improve your tutor overnight: a better model is a new app version, and the model is most of the download.

[Routine Genius @routine_genius]

1/ Four hundred days of a language app and you still can't order a coffee.

That isn't a discipline problem. You did the work, and you did it every day. You were practising the wrong thing, beautifully.

[Routine Genius @routine_genius]

8/ The costs come from that same decision and I'd rather you hear them from me. No account means no sync, no "continue on the iPad," no password reset — there's no password. If the phone goes in a river, your progress went with it.