Apple developers who make apps for the iPhone and iPad earned 30% more in 2017 than a year earlier, though it was still a slowdown from growth in 2016.

Developers who make apps for iOS earned US$26.5bn in 2017, Apple said in a statement on Thursday, as users snapped up breakout hits including games like Animal Crossing: Pocket Camp, and Monument Valley 2. In 2016, developers earned $20bn, a 40% increase from the year earlier.

Apple said its App Store had a record-breaking holiday season, culminating in $300m in purchases made on New Year’s Day 2018, up from $240m in the prior year.

Developers typically get 70% of that revenue, though the proportion increases to 85% after customers have completed a year’s subscription to an app. Consumers spent more than $890m over the seven days starting on Christmas Eve.

App Store sales growth may serve as an indicator of iPhone demand, since new owners are more inclined to spend money in the marketplace in the days after they get a new handset.

Investors are playing close attention to any indicators of demand for the iPhone X ahead of Apple earnings on 1 February, when the average sales price the company publishes will indicate whether customers are preferring the $999 top-of-the-line handset to cheaper models.

Apple has been prioritising its services business, which includes the App Store, as global smartphone sales slow. Services usually generate more profitable revenue, and also tie users more closely to their iPhones. — Reported by Alex Webb, (c) 2017 Bloomberg LP