Wikipedia has a List of mergers and acquisitions by Apple that's a pretty interesting read. It seems it takes about 2 years for an acquisition to make it into a product (maybe a little less).
For example, in April 2005 they bought FingerWorks and two years later the iPhone came out touting their multi-touch technology. Siri was released in Oct 2011, about a year and half after their acquisition of the company Siri in April 2010. TouchID appeared on the iPhone in Sept 2013 only 14 months after Apple bought AuthenTec.
I'm guessing some of Siri's new smarts announced this week came from their integration with Cue, acquired in oct 2013. Apple bought HopStop.com which did transit stuff in July 2013 and this week they (finally) announced transit support is coming in Maps. The new News app probably comes from Prss, which they acquired only last Sept.
So what might we expect to see from Apple given more recent acquisitions?
- LuxVue made low power micro-LED displays. The new MacBook sports " the thinnest, most energy-efficient Retina display ever on a Mac" with innovative pixels. Maybe that's it, maybe there's more to come.
- Dryft made digital keyboards and was acquired last Sept. Maybe the new iOS 9 has some lineage from them but their tech seemed more about sensing where your fingers are and putting the keyboard there and not repeating keys if you're just resting your fingers on the glass. I'm expecting way better virtual keyboards from Apple, particularly if they integrate ForceTouch into them.
- Just last month Apple bought Metaio which made augmented reality software. That could be very interesting. I'm guessing they'll combine it with their various map acquisitions.