Accelerate your key learnings of modern Android app development with KMM

Where other technologies abstract away or completely replace platform-specific app development, Kotlin MultiMobile is complementary to existing platform-specific technologies and is geared towards replacing platform-agnostic business logic. It’s a new tool in the toolbox as opposed to replacing the toolbox. This talk would take you on a hitch-hiking journey across building apps for Android and iOS all in one big repository with a shared domain. We would discuss how to get started, what the future is like, and how to build faster with tips and tricks of the trade.

Transcript

1. Accelerate your key
   learnings of modern
   Android app
   development with
   KMM
   Google Developers
   

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2. Android GDE

   🛠 Senior Manager Android - Viacom18

   🔊 Speaker

   🌎 Globe Trotter

   🍻 Beer enthusiast
   🎯https:/
   /androiddev.social/@aditlal
   🔗aditlal.dev
   

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4. a wild idea to build apps pops!
   develop for Android and iOS
   

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5. ‣ hire a team - Android and iOS
   ‣ de
   fi
   ne requirements
   ‣ plan roadmap for development
   ‣ develop and maintain and test apps
   ‣ production validation
   ‣ cross-check parity among both platforms
   

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6. native
   ~2x the team
   the cost
   time spent in meetings
   time spent on development
   time spent on testing
   time spent on bug
   fi
   xing
   

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7. a wild idea to build apps pops!
   develop for Android and iOS
   

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8. a wild idea to build apps pops!
   and web
   develop for Android and iOS
   

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9. native + web
   ~3x the team
   the cost
   time spent in meetings
   time spent on development
   time spent on testing
   time spent on bug
   fi
   xing
   

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12. let’s
    fi
    nd a solution that works on all
    platforms.
    

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13. let’s
    fi
    nd a solution that works on all
    platforms.
    

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14. 2006 2008 2011 2012 2013 2015 2017 2018
    . . . . . . .
    

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15. Cross-platform advantages
    

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16. Cross-platform advantages
    • smaller team/s
    • typically half of the cost needed on native
    • small learning curve for web developers
    

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17. Cross-platform advantages
    dis
    • Locked to the framework implementation of UI
    - new updates from the OS will take time to adapt
    • performance is not on par to native
    • One may end up also writing native code alongside
    • OS / device features are dependent on the fw
    support
    

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18. how do we have the best of
    both worlds?
    

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19. how do we have the best of
    both worlds?
    

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20. Kotlin
    • developed by JetBrains
    • open source
    • concise, safe, interoperable, dev tool-friendly
    • Supported/used by Google for Android
    Development
    • It is so much more than “just for Android”
    

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21. Kotlin
    K
    otlin multiplatform
    Using kotlin in projects to
    target more than one platform
    

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22. Kotlin multiplatform
    “Shared UI is a history of pain
    and failure. Shared logic is the
    history of computers.”

    

    - Kevin Galligan
    

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23. Kotlin multiplatform
    - language features
    - kotlin
    fi
    rst!
    - low risk
    - you decide what’s worth to share across projects
    - interoperability
    - consistency across platforms
    - strong community support
    

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24. Kotlin multiplatform
    /kot · lin mul · ti · plat · form /
    
    
    / kät' lin malti' platfôrm, kät'lin melti'platfôrm/
    
    
    noun
    optional, natively-integrated, open-source, code sharing platform, based on
    the popular, modern language kotlin. facilitates non-ui logic availability on
    many platforms.
    

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25. Kotlin multiplatform
    

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26. Kotlin multiplatform
    

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27. Kotlin multiplatform
    

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28. Kotlin multiplatform
    but how can they expect to communicate?
    

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29. Kotlin multiplatform
    but how can they expect to communicate?
    expect
    declared at common module 

    actual
    declared at android module
    declared at iOS module
    declared at ...
    

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30. Kotlin multiplatform
    Platform specif
    i
    c
    names?
    

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31. Kotlin multiplatform
    Platform | common
    

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32. Kotlin multiplatform
    commonMain
    src/commonMain/sample/Platform.kt
    
    
    expect object Platform {
    
    
    val name: String
    
    
    }
    

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33. Kotlin multiplatform
    src/commonMain/sample/Platform.kt
    
    
    expect object Platform {
    
    
    val name: String
    
    
    }
    

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34. Kotlin multiplatform
    src/commonMain/sample/Platform.kt
    
    
    expect object Platform {
    
    
    val name: String
    
    
    }
    targets: android and iOS or macOS

    de
    fi
    ne actual on android
    de
    fi
    ne actual on iOS

    de
    fi
    ne actual on macOS
    

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35. Kotlin multiplatform
    src/androidMain/sample/Platform.kt
    actual object Platform {
    
    
    actual val name: String = "Android"
    
    
    }
    platform-dependent code
    

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36. Kotlin multiplatform
    platform-dependent code
    actual object Platform {
    
    
    actual val name: String = “iOS"
    
    
    }
    src/iOSMain/sample/Platform.kt
    

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37. Kotlin multiplatform
    src/androidMain/sample/Platform.kt
    actual object Platform {
    
    
    actual val name: String = "Android"
    
    
    }
    platform-dependent code
    actual object Platform {
    
    
    actual val name: String = “iOS"
    
    
    }
    src/iOSMain/sample/Platform.kt
    

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38. Kotlin multiplatform
    platform-dependent code
    actual object Platform {
    
    
    actual val name: String = “macOS”
    
    
    }
    src/macosMain/sample/Platform.kt
    

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39. Kotlin multiplatform
    platform-dependent code
    import io.ktor.*
    fun main() {
    embeddedServer(Netty, 9090) {
    routing {
    get("/hello") {
    call.respondText("Hello, API!")
    }
    }
    }.start(wait = true)
    }
    src/jvmMain/kotlin/Server.kt
    

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40. Kotlin multiplatform
    

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41. Kotlin multiplatform
    Actual needs to match
    because obviously it does
    

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42. Kotlin multiplatform
    

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43. Kotlin multiplatform
    

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44. Common

    Kotlin
    Kotlin/JS
    JS code
    Kotlin/JVM
    JVM code
    Kotlin/Native
    Native code
    Kotlin multiplatform
    

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45. Kotlin multiplatform
    Kotlin
    How much do we share
    Multiplatform
    What makes most sense
    

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46. Kotlin multiplatform
    - strong community
    - a lot of people are using kotlin nowadays
    - Google and JetBrains are pushing Kotlin exclusively
    - you can ask questions directly at https://kotlinlang.slack.com
    conclusions
    

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47. - 2x faster to develop your features business logic
    - 2x faster writing unit tests
    - One tech stack
    - consistency achieved across platforms
    Kotlin multiplatform conclusions
    

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48. Kotlin multiplatform
    - start small, don’t try to reach 100% of shared logic
    - be extremely careful with all updates
    - IDEA, JDK, kotlin, libraries - everything.
    - keep versioning in mind
    Suggestions
    

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49. Kotlin multiplatform
    Kotlin Slack
    Kotlin Of
    fi
    cial
    Kotlin Training
    Kotlin by:
    - https://jakewharton.com/presentations/
    - http://antonioleiva.com/kotlin
    Resources
    

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50. Kotlin multiplatform
    https://github.com/joreilly/PeopleInSpace

    

    About
    Kotlin Multiplatform project with SwiftUI, Jetpack Compose, Wear Compose,
    Compose for Desktop, Compose for Web and Kotlin/JS + React clients along
    with Ktor backend.
    Resources
    

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51. AI-powered tooling
    for developers
    •How do I add camera support to
    my app?
    
    
    •I want to create a Room
    database.
    
    
    •Can you remind me of the
    format for javadocs?
    
    
    •What is dark theme?
    
    
    •What's the best way to get
    location on Android?
    

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52. What’s in store for future
    

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53. What’s in store for future
    

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54. Predictive Back Gesture
    Introduced in Android 13

    Predictive back gesture supported on phones , large
    screens and foldables.

    

    BackHandler in Compose

    OnBackPressedCallback | OnBackInvokedCallback
    

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55. Android design Hub
    https:
    / /
    android
    -
    developers.googleblog.com/2023/05/introducing
    -
    android
    -
    ui
    -
    design
    -
    hub.html
    
    
    

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56. Baseline Pro
    fi
    les improvements
    Performance is key to success in mobile apps.
    Baseline Pro
    fi
    les allow us to partially compile the app at install time, which helps
    get user paths optimized - helps improve runtime performance and launch times.
    

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57. M3 - Material 3
    

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58. .. and Much More
    

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59. Thats all folks!
    https:/
    /linktr.ee/aldefy
    

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