Comparison of blockchain e-wallet implementations

Sammanfattning: With the rise of blockchain technology and cryptocurrency, secure e-wallets also become more important. But what makes an e-wallet secure? In this report, we compare different aspects of ewallets to see which alternatives are secure and convenient enough to be used.This report contains comparative analyses of different implementation for e-wallets. The problem area is divided into three smaller areas: Key storage, authentication, and recovery. These problem areas have defined criteria for what is considered good qualities in each respective area.The results show that for key storage, the best options are, Android’s keystore/IOS’ secure enclave, offline storage or a hybrid hot/cold storage. For authentication, the best alternatives proved to be BankID and local authentication through the phone’s OS. Good Recovery alternatives include recovery seeds that recover the whole e-wallet or using multiple keys for both signing and recovery.The proof of concept made for this project uses three different storage methods with the authentication methods for each one and with the possibility of recovery in case a key should be lost. The storage methods used are offline storage thought QR-codes, online storage with firebase and local storage with Android keystore or Secure enclave. Authentication is done with Facebook/Google sign in or local authentication.