Developers, pay attention: Google has changed its ranking algorithm for mobile searches and will prioritize results for those brands with Android apps installed on the searcher's phone.
The announcement (read more here) doesn't come as a surprise, as Google is constantly working to improve the search experience. This is a smart move by Google to ensure that developers don't neglect the Android ecosystem, especially as many mobile devs first release an app for iOS and then shift to Android.
The move also has real implications for the travel app development roadmap, especially as smartphones have become the central hub for Internet access for many users. Rather than turn to the desktop, searches are increasingly completed via mobile. The limited screen size relative to desktop means that search providers such as Google must work to deliver the right information as fast as possible.
Deep linking is the new norm
If you've completed a search recently on Google, you will notice what's known as "deep links" on some websites that direct users to specific content pages. This is the same concept that will now be applied to Android apps.
The apps will be indexed so that the search algorithm knows specific points in the app that might be relevant to searches. For example, a search for "New Orleans restaurants" might return specific pages from apps that the user has on her phone. This could be reservation pages, ratings and reviews, and other content that reflects the search.
App Indexing begins immediately, with Google promising

to use information from indexed apps as a factor in ranking for signed-in users who have the app installed. As a result, we may now surface content from indexed apps more prominently in search.
To learn more about how to ready apps for deep-linking via App Indexing, Google has offered a developer guide here.
Mobile-friendliness is now a factor in determining ranking
In addition to providing direct links to content within installed apps, Google will also now consider mobile-friendliness in ranking results for mobile searches.
Google emphatically states that this new "ranking signal" will soon have an outsized impact on mobile search results:

This change will affect mobile searches in all languages worldwide and will have a significant impact in our search results. Consequently, users will find it easier to get relevant, high quality search results that are optimized for their devices.
These changes begin April 21, so you have a bit of lead time here to ensure that websites meet the criteria for mobile friendliness. Ignoring these changes could seriously disadvantage a brand's website in search, so don't procrastinate on this one!
Here are the resources that you need to make this change: Guide to creating mobile-friendly sites, mobile-friendly test for analyzing a few pages, and the Mobile Usability Report via Google's Webmaster Tools.
NB: Android lollipop image courtesy Shutterstock.