Android pro tips for advanced expert Android developers

Short summary of the Google I/O 2011 session "Android Protips: Advanced Topics for Expert Android App Developers". Full presentation can be found here.

6:35: the parallel Activity pattern: based on SDK version, start another "parallel" code line. Easy check to see what your SDK version is so you can distinguish use of more advanced APIs as for example available since HoneyComb.
8:20: use interfaces for backward compatibility
9:09: get real user feedback before launching. Note you can also of course use Analytics to log an exception!
10:38: example of doing A/B testing
11:35: use Android Market for beta testing. It seems there's no special facility for this in the market, you just have to control it yourself... e.g password protect, obscure the name.
12:31: But don't forget to protect your package name before someone else takes it! So upload and save it but don't publish it.
13:43: don't assume the default (natural) orientation on a device is portrait, e.g most tablets start in landscape. The orientation sensor's default is also 90degrees "off"
15:00: Don't track devices to detect unique installations. Give your app a unique id using a UUID, store it in the prefs.
20:00: the app's data has to be always fresh if possible, the user does not have to wait. See also this recent post: http://android-developers.blogspot.com/2011/06/deep-dive-into-location.html
25:51: how to get fresher data
32:00: make your services intelligent like do everything async, let it die asap
33:13: make your app psychic: leverage what the phone already knows, remembers what the user has told it. Like the Account Manager. Preferences should follow the user across devices and resets (which means storing them offline). Give users the ability to delete their preferences, using the Backup Manager to backup shared preferences.
38:21: intercept links using an Intent Receiver
39:25: make your apps adaptive. E.g: behave as expected, optimize for different user experiences. You can specify the IME keyboard behavior by setting the appropriate action (Go, Search, Send, Done etc). Use android:imeOptions for that
43:20: handle volume and playback buttons icw requesting audio focus for playback
47:10: provide translations for your app and title description to have it better found in people's native language
48:00: make your app smooth: make everything async. Loader and CursorLoader are available since HoneyComb.