Woodcoin Wallet Simple Payment Verification for IOS . It is an open source non-custodial wallet in which the users can back up their private keys and have total control of their funds. Woodcoin is a public ledger currency, a public blockchain, and a logarithmically growing money supply. This keeps transaction fees low and keeps the currency stable and secure for a much longer time than any other block chain currency. The LOG block chain is a log structured database with a logarithmic supply.