Resilio Sync is an open source tool to create a Dropbox-like file-syncing service. You can share a folder with anyone. Files are stored on the server (which can be your raspberry pi) and on all the other computers that you gave a secret key.
Install
There are a few steps you have to do to install it. This works on Raspberry pi 2 and 3. I’ve installed it most recently on Raspbian Stretch.
Add Resilio’s gpg key:
wget -qO - https://linux-packages.resilio.com/resilio-sync/key.asc | sudo apt-key add -Add Resilio’s repository to the apt sources.list:
sudo nano /etc/apt/sources.list deb [arch=armhf] http://linux-packages.resilio.com/resilio-sync/deb resilio-sync non-free
Now let’s install it:
sudo dpkg --add-architecture armhf sudo apt-get update sudo apt-get install resilio-sync
Most of it comes from Resilio Sync’s installing guide.