Data Synchronization

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Easchi adopts a storage structure where “one flashcard corresponds to one note file + one metadata file + one review history file.”

For power users with tens of thousands of flashcards—say, 30,000 cards—this translates to as many as 90,000 tiny files. If traditional file-by-file synchronization is used, it will trigger catastrophic network I/O latency.

Built-in Sync

Easchi provides a specifically optimized built-in sync solution:

1. Automatic Bundling & Merging: Before uploading, the sync engine automatically bundles and compresses fragmented flashcard data and review tracks into a highly efficient single data package.
2. Incremental & Full Backup: Hybrid full and incremental backups are performed on a per-vault basis, significantly boosting the sync speed of small files under weak network conditions.
3. Flexible Version Cleanup: Allows you to flexibly configure and clean up older historical versions to free up cloud storage space.

Why not provide manual, pure object storage sync?

If you completely avoid using the built-in sync, manually downloading hundreds of thousands of fragmented files in full before opening the app and uploading them in full after exiting will result in agonizingly long wait times. For the ultimate sync throughput and time efficiency, we strongly recommend using the built-in dedicated sync channel.

Custom Sync

If you choose not to use the built-in sync feature, it is recommended to use version control software like Git paired with a remote repository.

The reason is that the content of the flashcard history files grows continuously. If a synchronization method lacking automatic merging capabilities is used, it can easily cause local flashcard data to be overwritten incorrectly, thereby disrupting your review schedule and leading to partial data loss.