As of today, MetaMask is by far the most popular wallet for the Ethereum blockchain. It's available for mobile and as an extension for Firefox, Chrome, and Brave. After installation, it enables your browser to interact with the Ethereum network. Not only can you use it to store, send, and receive ether, but it also allows you to interact with decentralized applications running on Ethereum. I particularly like MetaMask as a developer because you can switch quickly between a test network, e.g., Rinkeby, and the Ethereum Mainnet. If you haven't already, go and download MetaMask here.