Wallet backup

[zubr]

Hi,

I understand that my mobile wallet (here: Coinomi) needs a backup in order to restore the wallet in case of loss or damage of my mobile device.

Three questions: 1) When I restore a wallet using a restore phrase (seed) by installing the app on a new mobile device, where does the app retrieve its backup data? Is everything stored somewhere in the Internet and downloaded on my phone during the restore phase?

2) What is exactly backup'ed? Are these just the private keys that were stored in the wallet when I did a backup of my data?

3) Do I need to backup my data every time when I change something in the mobile wallet, e.g. when I add new funds to my existing coins or when I import new currencies (and thus generate new private keys) to the wallet?

Best Chris

[MintDice]

1) Above my pay grade, forgive me, good sir/lady. Ask nandibear
2) Yes
3)Only need to back up once or if you create a new receiving address inside that wallet and send something to it.

[nandibear]

Hi,

I understand that my mobile wallet (here: Coinomi) needs a backup in order to restore the wallet in case of loss or damage of my mobile device.

Three questions: 1) When I restore a wallet using a restore phrase (seed) by installing the app on a new mobile device, where does the app retrieve its backup data? Is everything stored somewhere in the Internet and downloaded on my phone during the restore phase?

2) What is exactly backup'ed? Are these just the private keys that were stored in the wallet when I did a backup of my data?

3) Do I need to backup my data every time when I change something in the mobile wallet, e.g. when I add new funds to my existing coins or when I import new currencies (and thus generate new private keys) to the wallet?

Best Chris

Regarding question #1:

I can only provide a simple answer (anyone else please feel free to jump in with a more technical response).

The Bitcoin.com wallet is a lightweight client (as opposed to a full node or full client).

Your seed generates addresses and private keys.

You can use a lightweight client (e.g., Bitcoin.com wallet) to send transactions on the blockchain (without downloading and saving the ever growing, in size, blockchain as a full node or full client does) from addresses which you have the corresponding private key to.

Lightweight wallets are able to function because they are connected (through a server) to a full node.

Your seed (and private keys) are not stored on the server. When you restore your wallet you are essentially just putting your seed and keys back into your lightweight client (e.g., Bitcoin.com wallet) so that you can send transactions on the blockchain. The wallet also populates with other data from the blockchain itself such as past transactions. (Please ask others for more technical details regarding BIP39 and how it works.)

There is some data stored on the server that your lightweight wallet is connecting to. However, it's not your privates keys or seed or anything else that would give someone the ability to send transactions. Moreover, it's not any data that you specifically, or exclusively, need to restore your wallet. For example, you can download a standalone (i.e., a file that you can run offline, on your own computer, without internet connection) and type in your seeds words and it will spit out a list of addresses and privates keys.