I've used Coinbase for a few years and have watched the site evolve and expand to include an app. It's pretty straightforward to use, with no frills, no bells nor any whistles. It's simple and easy to use to track, buy, or sell any of the cryptocurrencies hosted on their exchange. Also easy to withdraw and deposit. It's a solid standalone site, with a really easy to use app with a clean interface. The imposed security features and protocols I've had to adhere to over time have made Coinbase operate and feel like a secure trading platform.