One of the fundamental differences between Android and every other mobile operating system is the practically unrestricted capability to run services. Without this freedom we could not enjoy something as powerful as a homescreen widget or as straight-forward as a Twitter client with background updates. Aside from games and very simple utilities, it’s becoming increasingly rare to find an app that doesn’t run a service, at least for a short span of time.
Flash may have died a slow and agonizing death on Android, but it did not depart without leaving its heir apparent. Adobe's lighter-weight successor was built to better handle touchscreen interfaces, lower power processors, and to support applications living independently from a web browser. While the platform hasn't been a high-flying success on Android or iOS, it does play host to a few popular games like Machinarium. Exactly three years and one day after first appearing on the Android Market, Air has been updated to v3.9 and now includes support for multi-threading, background tasks, and xxhdpi icons.