NFC Archiver

A distributed data archive system using NFC tags. Store files across multiple NFC tags and restore them later.

Split any file into parts and write them to NFC tags. Scan the tags in any order to reassemble and restore the original file.

Features:

* File archiving — split any file into parts for writing to NFC tags

* Text archiving — store text messages across NFC tags

* Restoration — scan tags in any order and assemble the original file

* Restored files — open them in another app, save them to Downloads or any folder, or share them

* Compression — optional GZIP compression to reduce the number of tags needed

* Encryption — AES-256-GCM encryption with password protection (PBKDF2 key derivation)

* Offline operation — no network connection required

* Chameleon Ultra — connect a Chameleon over Bluetooth and use it instead of the phone's NFC radio

* MIFARE Classic 1K — 752 usable bytes per card, with a Chameleon or a phone whose NFC chipset supports it

* Card inspector — dump a card block by block with a decoded NFAR header and CRC check (needs a Chameleon)

Supported NFC Tags:

* NTAG213 (144 bytes)

* NTAG215 (504 bytes)

* NTAG216 (888 bytes)

* MIFARE Ultralight (48 bytes)

* MIFARE Ultralight C (144 bytes)

Uses the NFAR v1 binary format with a 28-byte header, CRC32 integrity checking, and UUID-based archive identification. Chunks can be scanned in any order and are validated automatically.