When comparing BitTorrent Sync vs Seafile, the Slant community recommends Seafile for most people. In the question“What are the best personal file-syncing solutions?” Seafile is ranked 4th while BitTorrent Sync is ranked 11th. The most important reason people chose Seafile is:
Seafile community edition is licensed under GPLv2 with source code available on [GitHub](https://github.com/haiwen/seafile).
Ranked in these QuestionsQuestion Ranking
Pro No service cost, storage limits, perfomance limits or privacy concerns
Since BitTorrent Sync uses P2P technology and does not require an external server from a third party, the only limitation if what is available to the user.
Pro Clients on most platforms available
BitTorrent Sync is available for Windows, Mac, Linux, Android, iOS, Windows Phone and BSD.
Pro Self hosted
If user opens a malicious website that website may create users to access your data ("When registering, http traffic for creating new user on loopback http://127.0.0.1:8888"). Being self hosted one does not need to open a site to get to their files.
Pro Free and open source
Seafile community edition is licensed under GPLv2 with source code available on GitHub.
Pro Client-side encryption
All files are transferred with AES 128 bit encryption.
Being proprietary, it's harder to audit.
Con Has some risky attack vectors
The only really good thing it has is that data is self-hosted (i.e. hosted on a server running on your machine with data that are on your machine).
- If user opens a malicious website that website may create users to access your data ("When registering, http traffic for creating new user on loopback http://127.0.0.1:8888")
- GetSync.com server receives many (all?) hashes in cleartext when sharing the directory.
Con Pro version for a fee
Selective Sync only available in Pro version. Business use is not allowed with free and Pro versions.
Con One peer of your network always has to be online to propagate changes to the other peers
Con Android app drains battery fast
Con Requires maintenance
You have to manually keep the server and clients up to date.