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MyEtherWallet.
Developers of the wallet Myetherwallet claim that it is not an online repository of broadcasts but only a service that helps you get through the browser access to coins stored in your computer's memory. In this case, the user doesn't risk using his own resources since they're not transferred for storage to a third-party resource and all access keys are stored only from him. Uniquely, the service has its advantages, so many users prefer it to other wallets.