Google's iOS apps already do a good job at seamlessly moving you back and forth between them to get things done — tapping a Google Now card that shows you directions to work will drop you right into Google Maps, for example. Now, the company is extending that functionality to third-party apps on iOS. As of today, Google can index apps in its search results and provide users with direct links into those apps. You'll need to search using either the official Google app or the iOS version of Chrome, but your results will include links to relevant apps you may have installed — tapping that app link will bring you right into the app where you'd expect to be.
The obvious example Google presents is OpenTable — you can tell Google you need a reservation at a particular restaurant and then tap the OpenTable icon in the search results to get straight into OpenTable at the specific restaurant you were looking for. There's a "return to Google" bar at the top to bring you back to your search results directly if the app doesn't have what you're looking for, a feature that's similar to how Google's own apps let you jump back and forth between them.
This is a feature that's existed for a long time on Android, but Google has been pretty relentless about having its services work near-identically between the two dominant mobile platforms —as much as iOS will allow, anyway. Google says that iOS apps will begin showing up in search results "in the coming weeks," provided that you're signed into your Google account when performing the search. If you're a developer and want to make sure your app shows up in Google search results, the company offers a few tips at the end of its blog post announcing the feature — and there's also a session at Google I/O later this week to help developers get their apps indexed by Google.