Looking back on the year in mobile, companies were all about changing things up. As the move to mobile grows more prevalent on an ever-expanding number of devices led by smartphones and tablets, companies such as Apple and Google rolled out new OSes with major overhauls in aesthetic, design and UI to match them.

In September, Apple launched iOS 7 with two new iPhones—the 5s and 5c—to run it on. iOS 7 is the first major UI style and UX change for the device, ushering in a new look and feel with a new color scheme, sharper UI geometry and more layered depth, plus new features like a control center for the OS.

Google saw the iOS 7 hype and raised it in October with a cross-brand marketing campaign, partnering with Nestlé to promote its new Android OS, KitKat 4.4. When it finally dropped on Halloween, KitKat came bearing new frameworks and APIs for faster multitasking, translucent system UI styling, and built-in Google Now functionality on the home screen. KitKat was released with the vision to reach “the next billion Android users,” extending Android to Smart TVs and wearable technology.

Behind the scenes, developer preferences for mobile app development continued to shift away from native toward hybrid HTML5. Web and hybrid approaches are becoming more popular with developers, as a Telerik survey in October showed that the combination of HTML5 and JavaScript is the top choice for building cross-platform apps. While HTML5 is still closing the gap in terms of APIs, performance, education, tools and marketing, the native “one-size-fits-all” mobile development solution is gradually being left by the wayside.

Further down on the totem pole, Microsoft played catch-up in a big way throughout 2013. It merged Windows Phone and Windows Store development as part of its push to create a single app store for all platforms. (Not to mention bolstering its mobile footprint by acquiring Nokia’s devices and services business.) Its efforts were beginning to pay dividends, with a November poll of mobile developers showing that 32%—double that of 2013—plan to create Windows Phone apps next year.

The year in mobile wouldn’t be complete without mentioning one of 2013’s biggest buzzwords: wearables. Google Glass, Samsung’s Galaxy Gear smartwatch, and a host of other wrist and eyewear devices are in various stages of development, as new SDKs and even OSes like KitKat try to get a handle on the coming wearable boom. This year, wearable technology sits at the bottom of our mobile wrap-up. Next year, it may well be at the top.