Electrum-grs is a lightweight "thin client" groestlcoin wallet Windows, MacOS and Linux based on a client-server protocol. Its main advantages over the original Groestlcoin client include support for multi-signature wallets and not requiring the download of the entire block chain.

If you are an ordinary user of Groestlcoin and simply want the convenience of a web wallet with the security of a real application and support for multi-signature, then Elecrum-GRS is the right choice for you.Changelog Electrum-GRS 3.2.3:• hardware wallet: the Safe-T mini from Archos is now supported.• BIP39 seeds: if a seed extension (aka passphrase) contained multiple consecutive whitespaces or leading/trailing whitespaces then the derived addresses were not following spec. This has been fixed, and affected should move their coins. The wizard will show a warning in this case.• Revealer: the PRNG used has been changed (#4649)• fix Linux distributables: 'typing' was not bundled, needed for python 3.4• fix #4626: fix spending from segwit multisig wallets involving a Trezor cosigner when using a custom derivation path• Several other minor bugfixes and usability improvements.Changelog Electrum-GRS 3.2.2:• Qt GUI: seed word auto-complete during restore• performance improvements (wallet, and Qt GUI)• hardware wallets: show debug message during device scan• add regtest support (via --regtest flag)• other minor bugfixes and usability improvements• If present, libsecp256k1 is used to speed up elliptic curve operations. The library is bundled in the Windows, MacOS, and Android binaries. On Linux, it needs to be installed separately.• Transactions that are dropped from the mempool are kept in the wallet as 'local', and can be rebroadcast. Previously these transactions were deleted from the wallet.• The scriptSig and witness part of transaction inputs are no longer parsed, unless actually needed. The wallet will no longer display 'from' addresses corresponding to transaction inputs, except for its own inputs.• The partial transaction format has been incompatibly changed. This was needed as for partial transactions the scriptSig/witness has to be parsed, but for signed transactions we did not want to do the parsing. Users should make sure that all instances of Electrum-GRS they use to co-sign or offline sign, are updated together.• Signing of partial transactions created with online imported addresses wallets now supports significantly more setups. Previously only online p2pkh address + offline WIF was supported. Now the following setups are all supported:- online {p2pkh, p2wpkh-p2sh, p2wpkh} address + offline WIF,- online {p2pkh, p2wpkh-p2sh, p2wpkh} address + offline seed/xprv,- online {p2sh, p2wsh-p2sh, p2wsh}-multisig address + offline seeds/xprvs(potentially distributed among several different machines)Note that for the online address + offline HD secret case, you need the offline wallet to recognize the address (i.e. within gap limit). Having an xpub on the online machine is still the recommended setup, as this allows the online machine to generate new addresses on demand.• Segwit multisig for bip39 and hardware wallets is now enabled (both p2wsh-p2sh and native p2wsh).• Ledger: offline signing for segwit inputs (#3302) This has already worked for Trezor. Offline segwit signing can be combined with online imported addresses wallets.• Added Revealer plugin. ( https://revealer.cc ) Revealer is a seed phrase back-up solution. It allows you to create a cold, analog, multi-factor backup of your wallet seeds, or of any arbitrary secret. The Revealer utilizes a transparent plastic visual one time pad.• Fractional fee rates: the Qt GUI now displays fee rates with 0.1 gro/byte precision, and also allows this same resolution in the Send tab.• Hardware wallets: a "show address" button is now displayed in the Receive tab of the Qt GUI. (#4316)• Trezor One: implemented advanced/matrix recovery (#4329)• Windows: use dnspython to resolve dns instead of socket.getaddrinfo (#4422)• Importing minikeys: use uncompressed pubkey instead of compressed (#4384)• SPV proofs: check inner nodes not to be valid transactions (#4436)• Qt GUI: there is now an optional "dark" theme (#4461)• Several other minor bugfixes and usability improvements.• Fix DNS resolution on Windows• Fix websocket bug in daemonChangelog Electrum-GRS 3.1.2:• Capital gains: For each outgoing transaction, the difference between the acquisition and liquidation prices of outgoing coins is displayed in the wallet history. By default, historical exchange rates are used to compute acquisition and liquidation prices. These values can also be entered manually, in order to match the actual price realized by the user. The order of liquidation of coins is the natural order defined by the blockchain; this results in capital gain values that are invariant to changes in the set of addresses that are in the wallet. Any other ordering strategy (such as FIFO, LIFO) would result in capital gain values that depend on the presence of other addresses in the wallet.• Local transactions: Transactions can be saved in the wallet without being broadcast. The inputs of local transactions are considered as spent, and their change outputs can be re-used in subsequent transactions. This can be combined with cold storage, in order to create several transactions before broadcasting them. Outgoingtransactions that have been removed from the memory pool are also saved in the wallet, and can be broadcast again.• Checkpoints: The initial download of a headers file was replaced with hardcoded checkpoints. The wallet uses one checkpoint per retargeting period. The headers for a retargeting period are downloaded only if transactions need to be verified in this period.• The 'privacy' and 'priority' coin selection policies have been merged into one. Previously, the 'privacy' policy has been unusable because it was was not prioritizing confirmed coins. The new policy is similar to 'privacy', except that it de-prioritizes addresses that have unconfirmed coins.• The 'Send' tab of the Qt GUI displays how transaction fees are computed from transaction size.• The wallet history can be filtered by time interval.• Replace-by-fee is enabled by default. Note that this might cause some issues with wallets that do not display RBF transactions until they are confirmed.• Watching-only wallets and hardware wallets can be encrypted.• The SSL checkbox option was removed from the GUI.• The Trezor One and T hardware wallet is now supported.• The Ledger hardware wallet is now supported.• BIP84: native segwit p2wpkh scripts for bip39 seeds and hardware wallets can now be created when specifying a BIP84 derivation path. This is usable with Trezor and Ledger.• Windows: the binaries now include ZBar, and QR code scanning should work.• The Wallet Import Format (WIF) for private keys that was extended in 3.0 is changed. Keys in the previous format can be imported, compatibility is maintained. Newly exported keys will be serialized as "script_type:original_wif_format_key".• BIP32 master keys for testnet once again have different version bytes than on mainnet. For the mainnet prefixes {x,y,Y,z,Z}|{pub,prv}, the corresponding testnet prefixes are {t,u,U,v,V}|{pub,prv}. Note that due to this change, testnet wallet files created with previous versions of Electrum must be considered broken, and they need to be recreated from seed words.• A new version of the Electrum-GRS protocol is required by the client (version 1.2). Servers using older versions of the protocol will not be displayed in the GUI.Changelog Electrum-GRS 3.0.6:• Moved away from Linux binary file. Users must compile from source now.• Moved away from electrum-grs-server codebase to electrumx-grs 1.2• The source code is relicensed under the MIT Licence• Separation between plugins and GUIs• The command line uses jsonrpc to communicate with the daemon• New command: 'notify