🏰

LifeArc Β· v2.1

"My fortress, my data."

Your phone
is your server.

Encrypted data vault, personal calendar, time capsules and notes. All offline, all on your phone. No cloud, no third party.

Explore modules πŸ“¬ LifeArc Receiver β†’
Android + iOS React Native AES-256-GCM Offline-first

Beta

Download Apps

Scan the QR code or tap the button β€” download starts immediately.

Loading versions…

⚠️ Beta β€” APK files available for direct download. iOS coming soon.

Three principles

Built on three foundations

πŸ›‘οΈ
Absolute privacy
No communication with external servers (exception: Time Capsule verifies time). Your data is yours and stays with you only.
⚑
Offline first
Everything works without internet. Your phone is the only server. 24/7 availability without dependence on third-party services.
πŸ“
Format independence
Data as plain JSON or encrypted .arc export. No proprietary cloud format.

App modules

Five modules, one ecosystem

Each module works independently, but together they form a complete system for managing your digital life.

πŸ—„οΈ
Module 1
Vault Manager
Your data is stored in local .vault files β€” plain JSON on your device. Export to an encrypted .arc file at any time. Sharing via AirDrop, Bluetooth, USB, email.
Create vault Export .arc Import .arc AirDrop / Bluetooth Auto-save Biometrics on delete 20 MB limit
πŸ“…
Module 2
Calendar
Full-featured personal calendar integrated with your vaults. Five views, swipe navigation, hourly timeline and import from Google Calendar via .ics.
Day / Week / Month Year / Agenda Swipe navigation Import .ics Recurring events Timeline 6:00–23:00
⏳
Module 3 β€” Core feature
Time Capsules
A message, photo or note encrypted with AES-256-GCM. The capsule unlocks only when it should β€” changing the clock won't help. Verified via 4 independent time servers in parallel.
AES-256-GCM 4 time servers Offline tolerance Text + photos Date down to the minute Export .arc
Detailed capsule description ↓
πŸ“
Module 4
Notes & TO-DO
Free-form text or structured tasks with checkboxes. Assign priority, tag items and directly convert a task into a calendar event.
Notes Tasks with checkbox Convert to event Priority: High / Medium / Low Tags: #garden #family… Sort: newest first
βš™οΈ
Module 5
Settings
Language, theme, biometric lock and external calendar import. In-app guide loaded from GitHub with offline cache.
Czech / English Dark / Light theme Face ID / Fingerprint Import .ics In-app guide

Core feature β€” in detail

How capsule unlocking works

A capsule unlocks only when both conditions are met simultaneously. No exceptions, no password recovery.

1
πŸ“…
Exact time verification
Parallel query to 4 time servers. The first successful response decides.
Condition 1
2
πŸ”‘
Correct password
AES-256-GCM decryption. Without the password, the content is unavailable.
Condition 2
βœ—
πŸ•°οΈ
System clock manipulation
Manipulation detected. Capsule stays locked. State: clock_went_back
Blocked
?
πŸ“Ά
Offline fallback
No internet: estimate time from last verified check + configured tolerance (6h / 24h / 48h / Never).
Per-capsule
βœ“
πŸ”“
Capsule content unlocked
Text, photos, audio β€” all decrypted locally. Nothing leaves your phone.
Unlocked

Time servers

worldtimeapi.org
Primary
Cloudflare trace
Backup
google.com HEAD
Backup
timeapi.io
Backup

Interface preview

What LifeArc looks like

Clean dark interface. Each module has its own colour. The left card border is the visual signature of the app.

9:41β–ͺβ–ͺβ–ͺβ–ͺ
LifeArc Β· Capsules
My capsules
3 active Β· 1 unlocked
πŸ”’
Letter for 18th birthday
Locked
Opens: Jun 15, 2034
4382 d
14 h
πŸ”’
Letter to my future self
Locked
Opens: Jan 1, 2030
1385 d
8 h
πŸ”“
Grandma's recipe
Unlocked
Unlocked: Jan 1, 2025
Read β†’
πŸ—„οΈ
Vaults
πŸ“…
Calendar
⏳
Capsules
πŸ“
Notes
βš™οΈ
Settings
9:41β–ͺβ–ͺβ–ͺβ–ͺ
LifeArc Β· Vaults
My vaults
2 open
πŸ—„οΈ
Personal records
Open Β· 124 records
πŸ’Ό
Work projects
Open Β· 48 records
+ New vault
πŸ—„οΈ
Vaults
πŸ“…
Calendar
⏳
Capsules
πŸ“
Notes
βš™οΈ
Settings

Security model

Encryption without compromise

Technical details belong in the text, not in footnotes. Here they are.

πŸ”
AES-256-GCM
Military-grade encryption standard. Authenticated encryption β€” protects both content and data integrity.
// Encryption parameters
Algorithm: AES-256-GCM
Salt: 16 B random
Nonce: 12 B random
Auth tag: 16 B
Format: base64
πŸ”‘
PBKDF2 β€” key derivation
The password is never the key directly. PBKDF2 with SHA-256 and 100,000 iterations slows down brute-force attacks.
// Key derivation
Algorithm: PBKDF2
Hash: SHA-256
Iterations: 100 000
Library: @noble/hashes
πŸ“±
Local data
Vaults are stored as plain JSON. Philosophy: your phone is personal and Full Disk Encryption protects it. A password on every launch would be an unnecessary barrier.
πŸ“¦
Transport
No cloud. Data is transferred manually as an encrypted .arc file. Without the password, the file is unreadable.

Data transfer diagram

πŸ“±
Phone A
sender
β†’ encrypted .arc
AES-256-GCM
πŸ“„
deti.arc
encrypted
β†’ physical transfer
no internet
πŸ“±
Phone B
recipient
✈️ AirDrop
πŸ“‘ Bluetooth
πŸ’Ύ USB / SD card
πŸ“§ Email
πŸ”Œ USB flash drive

About the project

Tech stack

Built on proven open-source libraries. No black-box dependencies.

Layer Technology
Framework React Native + Expo SDK 55 v55
Language TypeScript β€” strict mode
Encryption @noble/ciphers + @noble/hashes β€” pure JavaScript, no native dependencies
State management Zustand
Platform Android + iOS
Network Offline-first Β· time check via multi-server pool
i18n Custom JSON hook β€” CS + EN
Author Petr VeselΓ½ (Petr Bum VeselΓ½)