Apple's (Nasdaq: AAPL) iTunes has recently celebrated its 15th birthday and the platform appears to still be performing well versus peer Spotify, though Spotify does appear to be gaining some ground.

Global Web index commented that 17 percent of Internet users outside of China are using iTunes, versus 11 percent for Spotify. Those numbers compare with 19 percent and 9 percent, respectively, recorded for the end of Q314.

GWI also noted that 40 percent of Internet users said they would prefer to subscribe to a streaming membership rather than pay to own products, meaning iTunes could be challenged in the coming years. Which is a good thing Apple now has iTunes Radio.

Shares of Apple are up around 0.4 percent Wednesday.