[buildanduse]

Great question - probably three differences: 1) Syncthing is storage only - Diode has dDrive for storage, but also supports N other use cases as a true web3 backbone candidate (e.g. currently deployed: video streaming, VPN, decentralized web hosting, remote SSH, etc...) 2) Syncthing uses community relays/nodes without any incentive structure - it limits the scale of the network. Diode implements a relay incentive in proportion to the traffic handled (which is somewhat predicated on the QoS the relay is able to provide) 3) Syncthing is a closed system (an impact of #1), so it can't do things like link sharing, web viewers, etc... whereas Diode is able to provide all those things fully decentralized

There are certainly also specific UX/functionality differences on how the apps are implemented, but those are probably the macro considerations.