How synchronisation work


I’m not sure how sync work on ankidroid.
I’ve downloaded a few decks from the server, modified some of them and created some of my owns, using my phone. Now I want to synchronise all this with my computer.
When I try to activate the sync from the phone, a warning message appears: “Are you sure you want to overwrite the existing data on the server?” I assume this concerns the original decks I have downloaded, so I haven’t tried it further.
Is there a way to just synchronize the data on the phone and the computer, without overwriting anything and keep it private?
Best regards

Do you have data (reviews, decks, cards…) on your computer that you don’t have on your phone? If no, it’s safe to overwrite. You will not lose anything that’s on your phone, only what’s on the server and your computer.
If yes and you want to keep that data, it’s a bit more complicated. (Say if that’s the case and you need more instructions.)


Thanks for your answer!
No, there is no data so far on the computer. Just to understand:

  • If I synchronize, the data can be accessed by someone else?
  • Does it alter the original data on the server (which weren’t mine)?

“Data on the server” here refers only to what you have synchronised over your personal profile. It’s like your personal storage room and only you and the caretaker (Anki staff) have a key.
Sharing decks is an entirely different mechanism and you don’t have to worry about doing that accidentally. If you have downloaded a deck, you have now a unique copy that isn’t linked in any way to the deck on Ankiweb.

Thanks a lot, everything’s clear now!