Alpha Vantage have real-time intraday as well as historical daily time series in JSON format. Accessing the data requires an API key but it is free.
Caveat: I have not yet used Alpha Vantage myself. The focus of my work requires long daily data series and for that Quandl (or, while it lasted, Yahoo) is better because (unlike Alpha Vantage) it provides both split-adjusted and un-adjusted data, which is helpful for tracking corporate actions etc.