Quiet apps. Built to be trusted.

Pacelli Labs makes small, careful apps for iPhone. They work offline, collect nothing they do not need, and will be published here as open source.

iPhoneFreeNo adsNo trackingOffline firstOpen source soon
01 / The apps

Four apps, each doing one thing well.

What each app is for, and how it works under the hood.

Pacelli icon
01

Pacelli

Household organiser

Tasks, shopping checklists, weekly plans and a household manual, shared between everyone you live with.

  • End-to-end encrypted. Household content is encrypted on your device before it is stored. The server holds ciphertext it cannot read.
  • Shared, in sync. Invite members by email and every change appears for everyone in the household.
  • Start as a guest. No account needed to try it. Sign in later to keep your data across devices.
  • Yours to take or destroy. Export a full backup as JSON at any time, or burn all data, account included, in one flow.
App StoreEnglish, Spanish, ItalianiOS 26
Pacelli task list
JK Graphic Editor icon
02

JK Graphic Editor

Photo darkroom

A professional raw developer that runs entirely on your iPhone. Your photos never leave the device.

  • Develops in linear light. A filmic tone curve keeps colours true, recovers highlights smoothly and never shifts hues.
  • Auto that checks itself. After developing, it measures the result for clipped highlights, crushed blacks, colour casts and oversaturation, and corrects them before you see it.
  • Refines, never undoes. Looks keep the camera's own white balance and exposure, then compare against the original so the edit is never worse.
  • True iPhone colour. Display P3 from import to export, RAW support for DNG, CR3, NEF, ARW, RAF and more.
App Store11 looksiOS 26
JK Graphic Editor developing a photo
Sapere icon
03

Sapere

Trivia that teaches

History, science, geography, the arts and more. Every answer comes with an explanation, a picture and its source.

  • Checked twice. Every question is verified against its source by one writer, then independently re-checked by another before it ships.
  • Learn as you play. Right or wrong, a short card explains the fact, credits the image and links to the source.
  • Nothing repeats too soon. Rounds of ten serve unseen questions first, so you see the whole collection before anything comes back.
  • Fully offline. Everything ships inside the app. It works on a plane or underground.
App StoreCollects no dataiOS 26
Sapere answer explanation
Hoshi Go icon
04

Hoshi Go

The game of Go

Play and learn Go, the ancient board game also known as Baduk or Weiqi, on 9x9, 13x13 and full 19x19 boards.

  • A complete rules engine. Captures, ko, suicide rules, handicap stones from 2 to 9 and proper area scoring with dead-stone marking.
  • Two ways to play. Pass-and-play with a friend on one phone, or against a bot made for beginners.
  • Learn by doing. Five short lessons with real capture puzzles take you from liberties to scoring your first game.
  • Private by design. No internet required, ever. It collects zero data.
App StoreFreeiOS 13+
Hoshi Go 19x19 game
02 / Principles

The rules every app follows.

A

Private by default

No ads, no tracking, no analytics. An account only when a feature truly needs one.

B

Offline first

Apps work without a connection. When data must sync, it is encrypted first.

C

Open by intent

Source code will be published here, reviewed project by project before release.

03 / Get in touch

Questions, bugs or ideas.

Write to us, or follow the organization on GitHub for new releases.