What Apple's market share looks like right before it launches iPhone 6S

Apple will launch its new iPhone 6S and iPhone 6S Plus phones in a few days time.

It's a tense time for the company: While new iPhones will bring new sales, those sales have not historically been as strong for the "S" update models. Customers prefer the all-new phones that carry new numbers, like the iPhone 5 and the iPhone 7 (expected in 2016).

Back in 2013-2014, when Apple launched its last S-model (the iPhone 5s), sales growth went through a "trough," as seen in this chart (click to enlarge). While sales still went up, the growth wasn't as strong as it had been before.

Just like last time, analysts and investors fear that Apple's sales growth may be hurt by the new S model. Partly because so many people have already bought the iPhone 6 (meaning there are fewer people who need a new phone right now). And partly because those who do need a new phone may be tempted to wait until next year for the even better models (Apple's phones are robust and last a long time).

Nonetheless, as we predicted back in February, iPhone 6 has put a huge dent in Android's dominance of the market (except in the US where, oddly, Android is stronger than ever). The challenge for iPhone 6S now is whether it can build on those gains or whether Android will simply recapture share while users wait for iPhone 7.

The following charts show historic market share trends for Apple v. Android, as tracked by Kantar.