To make the concept of reified concrete an example is in order: `Context.systemService()` in Android KTX uses reified to pass a "real" type via generics. No more passing classes to getSystemService!

https://github.com/android/android-ktx/blob/master/src/main/java/androidx/core/content/Context.kt#L37!

Docs: https://kotlinlang.org/docs/reference/inline-functions.html#reified-type-parameters

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Introduction to Wear OS by Google Development

Watch the full video with @hoitab here → goo.gl/zVbRN6

There is a wide variety of options when developing for Wear OS by Google (Formerly known as Android Wear). Apart from cross-platform development through phone notifications and Actions on Google, developers can leverage a wide range of development options - Wear apps, Watch faces and Complication Data Provider. Watch this video to get an introduction on development options open to you as a developer.

For more information, check out:

Complication Data Provider Code Lab → https://goo.gl/JxRyCV
Wear OS By Google Developer Site → https://goo.gl/j5mmqC

Improving conversions of your Android apps

Best practices and insights → https://medium.com/googleplaydev/increase-conversions-in-your-android-app-with-a-multidimensional-approach-e9dd5c659528

Getting conversions right is a complex yet highly important topic for Android developers. At Google Play, we’ve found that effective conversion optimization comes from focusing on three pillars: the basics, the organization, and the product. We’ll tackle these in detail to help you find a conversion optimization strategy that works for your business.

Using Kotlin and Java in the same project? Do you have classes with top-level functions or properties?

By default, the compiler generates the class name as “YourFileKt”. Change it by annotating the file with `@file:JvmName(“...“)`.

Doc: https://kotlinlang.org/docs/reference/java-to-kotlin-interop.html#package-level-functions

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Have a hand in the future of Android. Join a Google user experience study and give your feedback.

goo.gl/WqLSmd

Get acquainted with the ExoPlayer API by going on a journey to build an Android video player app that supports playlists, audio focus, and PIP #AndroidDev

Learn more: https://medium.com/@nazmul/building-a-video-player-app-in-android-part-1-5-d95770ef762d

Can’t wait to use lambdas to make new APIs?

Get in line.

Kotlin lets you specify a function as `inline` - which means calls will be replaced with the function body. Breathe and make lambda-based APIs with zero overhead.

Docs: https://kotlinlang.org/docs/reference/inline-functions.html

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Are your function arguments valid? Check before using them, with `require`. If they’re not valid an IllegalArgumentException is thrown.

Doc: https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/require.html

Is the state of your enclosing class correct? Use `check` to verify. It will throw an IllegalStateException if the value checked is false.

Doc: https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/check.html

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Google Developer Day is coming to GDC 2018

Learn more about our activities → https://goo.gl/QwMSjn

We’ve added three days of Googler talks taking place in our booth, Wednesday through Friday, where you’ll have a chance to ask our experts any questions. If you can’t make it in person, join the Google Developer Day livestream on Monday, March 19th starting at 10:00am PST.