Here are my slides from a talk I gave last week on what’s new and available for you as a developer in Google’s world. This talk gives a high level overview on the main APIs. If you wish to dive deeper on some of them, you will find many links in the slides.
The main story from these slides is that you can combain many services and APIs in order to built your new cool application. Take for example a case where you wish to have a social fitness application. You can integrate Google Maps into your mobile app so your user could keep track on where they did their actions. The backend for your mobile app can be done with Google App Engine & the rest of the Google Cloud Platform, jumpstarted with Google Cloud Endpoints feature of App Engine. In other words, you could built a powerful REST API with many other capabilities by these two services. Later, you can create a web version of your app with modern web tools like HTML5 and if you wish to live on the edge try Polymer and Dart. Both web & mobile versions of your app can provide convenient sign-on with “Sign-in with Google+.” You can build collaborative apps using the Google Drive Realtime API and give them the same functionality as when you see multiple users all editing in Google Docs simultaneously. And finally you can monetize your app with Google Wallet Instant Buy and retain and engage with your customers using the Wallet Objects API. I know this example is not the best, but I hope you ‘feel’ where I’m going with it. Good luck and built something amazing.