This contains list of links. Choose wisely.
https://android.jlelse.eu/build-a-bbc-world-news-aggregator-app-in-35-minutes-building-android-app-series-466cc7855abb
https://blog.mindorks.com/publishing-multiple-apks-on-google-play-b06bb9078aae
https://medium.com/@albur.ivan/reducing-android-apk-size-6e7d626e83a7
https://github.com/futurice/android-best-practices
https://infinum.co/the-capsized-eight/make-sure-users-have-the-latest-app-version-installed
https://github.com/ksughosh/AnimatedTextView
http://www.gadgetsaint.com/android/circular-images-glide-library-android/
https://infinum.co/the-capsized-eight/magic-constants-in-android-development
https://gist.github.com/gabrielemariotti/ad6672902464ee2392d0
https://github.com/hypertrack/hypertrack-live-android
http://www.tellmehow.co/android-mvp-pattern-example/
https://android.jlelse.eu/beginners-guide-to-better-android-development-b6d17d09d8da
https://gist.github.com/anggadarkprince/a7c536da091f4b26bb4abf2f92926594
https://android.jlelse.eu/custom-dialog-with-circular-reveal-animation-ef7dc77ba1e
https://android.jlelse.eu/customizing-switch-using-xml-ca0d37204a86
https://android.jlelse.eu/the-challenge-of-arranging-horizontal-textviews-231dc8f4bed5
https://github.com/DevAhamed/MultiViewAdapter
https://www.simplifiedcoding.net/expandable-recyclerview-android/
https://github.com/thoughtbot/expandable-recycler-view
https://github.com/hendraanggrian/recyclerview-expandable
Dagger 2 with Retrofit and OkHttp and Gson
Android — Adding badge or count to the navigation drawer
Learn to implement your first Android UI Library — Part 1
Custom Views and ViewGroups (Part 1)
https://android.jlelse.eu/building-custom-component-with-kotlin-fc082678b080
https://ask.ericlin.info/post/004-tricks-that-kotlin-can-help-to-write-andorid-custom-views/
Boost your Android productivity — Use Compound ViewGroups
The secret sauce behind uninstall tracking
ANDROID: Browsing Realm Database On Windows
Android, Using Navigation Drawer Across Multiple Activities: The easiest way.
Room + Time
https://medium.com/@chrisbanes/room-time-2b4cf9672b98
https://android.jlelse.eu/exploring-room-architecture-component-6db807094241
https://www.captechconsulting.com/blogs/android-architecture-components-room-persistence-library
https://medium.com/google-developers/7-steps-to-room-27a5fe5f99b2
https://medium.com/@ajaysaini.official/building-database-with-room-persistence-library-ecf7d0b8f3e9
https://medium.com/@magdamiu/android-room-persistence-library-97ad0d25668e
https://developer.chrome.com/multidevice/android/customtabs
https://segunfamisa.com/posts/chrome-custom-tabs
https://guides.codepath.com/android/Chrome-Custom-Tabs
https://labs.ribot.co.uk/exploring-chrome-customs-tabs-on-android-ef427effe2f4?gi=dd71edcfac88
http://www.androidhive.info/2016/12/android-working-with-webview-building-a-simple-in-app-browser/
https://gist.github.com/MohammadaliMirhamed/7384b741a5c979eb13633dc6ea1269ce https://firebase.google.com/docs/analytics/debugview https://firebase.google.com/docs/cloud-messaging/http-server-ref https://github.com/firebase/quickstart-android https://applikeysolutions.com/blog/how-to-send-a-push-notification-to-android-using-firebase https://www.codementor.io/flame3/send-push-notifications-to-android-with-firebase-du10860kb https://www.simplifiedcoding.net/firebase-cloud-messaging-android/ https://inducesmile.com/android/android-firebase-cloud-messaging-push-notification-with-server-admin-in-php-and-mysql-database/ https://shareurcodes.com/blog/send%20push%20notification%20to%20users%20using%20firebase%20messaging%20service%20in%20php
http://www.androidhive.info/2016/09/android-adding-facebook-comments-widget-in-app/
http://www.androidhive.info/2016/02/android-how-to-integrate-google-admob-in-your-app/
http://www.androidhive.info/2015/08/android-adding-sms-verification-like-whatsapp-part-1/ http://www.androidhive.info/2015/08/android-adding-sms-verification-like-whatsapp-part-2/
https://www.androidhive.info/2017/07/android-implementing-preferences-settings-screen/ https://medium.com/@JakobUlbrich/building-a-settings-screen-for-android-part-1-5959aa49337c#.h0a8vmhv5 https://github.com/consp1racy/android-support-preference http://alvinalexander.com/android/android-tutorial-preferencescreen-preferenceactivity-preferencefragment
http://blog.stablekernel.com/using-fragments-to-simplify-android-navigation-drawers https://github.com/codepath/android_guides/wiki/Fragment-Navigation-Drawer (http://guides.codepath.com/android/fragment-navigation-drawer ) http://stackoverflow.com/questions/34482404/how-to-add-an-item-to-a-menu-group-in-navigationview
https://www.edureka.co/blog/custom-spinner-in-android
https://www.codeproject.com/articles/1112812/android-alert-dialog-tutorial-working-with-time-pi
https://github.com/codepath/android_guides/wiki/Working-with-the-EditText
http://www.androidhive.info/2017/02/android-working-svg-vector-drawables/
http://clover.studio/2016/08/09/getting-current-location-in-android-using-location-manager/
https://developers.google.com/maps/documentation/android-api/ http://clover.studio/2016/08/11/developing-an-android-app-having-google-maps-part-1/
https://code.tutsplus.com/series/create-a-drawing-app-on-android--cms-704 http://valokafor.com/android-drawing-app-tutorial-part-1/
https://blog.mindorks.com/prdownloader-a-file-downloader-library-for-android-b9c5fc56a640
https://www.101apps.co.za/index.php/articles/using-the-downloadmanager-to-manage-your-downloads.html
https://www.codeproject.com/Articles/1112730/Android-Download-Manager-Tutorial-How-to-Download
http://blog.vogella.com/2011/06/14/android-downloadmanager-example/
http://sapandiwakar.in/building-a-music-player-app-for-android/ https://github.com/SueSmith/android-music-player
https://github.com/iammert/RadioPlayerService https://github.com/valdio/AudioPlayer https://www.sitepoint.com/a-step-by-step-guide-to-building-an-android-audio-player-app/ http://tutorialsface.blogspot.com/2014/07/music-player-with-notification-and-lock.html
http://www.tutorialsface.com/2015/08/android-custom-notification-tutorial/ http://www.tutorialsface.com/2015/09/simple-android-foreground-service-example/ http://sapandiwakar.in/android-media-player-lock-screen/
http://javaant.com/viewpager-with-circle-indicator-in-android/#.WRKgRYh97Dd
https://github.com/apl-devs/AppIntro https://medium.com/tangoagency/material-intro-screen-for-android-apps-c4317fbac923 https://www.spaceotechnologies.com/create-intro-slider-screen-android-app/ http://www.androidhive.info/2016/05/android-build-intro-slider-app/ https://github.com/TangoAgency/material-intro-screen https://github.com/apl-devs/AppIntro
http://stackoverflow.com/questions/34342816/android-6-0-multiple-permissions https://inthecheesefactory.com/blog/things-you-need-to-know-about-android-m-permission-developer-edition/en http://stackoverflow.com/questions/33139754/android-6-0-marshmallow-cannot-write-to-sd-card
https://github.com/MKergall/osmbonuspack (third party library) https://github.com/MKergall/osmbonuspack/tree/wiki (tutorial) https://github.com/MKergall/osmbonuspack/wiki/OSMNavigator (https://play.google.com/store/apps/details?id=com.osmnavigator)
https://github.com/osmdroid/osmdroid https://github.com/osmdroid/osmdroid/wiki https://github.com/osmdroid/osmdroid/wiki/Offline-Map-Tiles http://android-coding.blogspot.com/2012/06/example-of-implementing-openstreetmap.html https://stackoverflow.com/questions/tagged/osmdroid https://stackoverflow.com/questions/8136775/how-can-i-implement-offline-maps-using-osmdroid-by-saving-map-tiles-images-into/8286276#8286276
https://stackoverflow.com/questions/2661536/how-to-programmatically-take-a-screenshot-in-android?rq=1 http://www.viralandroid.com/2016/01/how-to-take-screenshot-programmatically-in-android.html https://stackoverflow.com/questions/20136121/android-how-to-take-screenshot-programatically https://stackoverflow.com/questions/30196965/how-to-take-a-screenshot-of-current-activity-and-then-share-it
http://www.mysamplecode.com/2013/02/android-animation-switching-activity.html http://www.androiddesignpatterns.com/2014/12/activity-fragment-transitions-in-android-lollipop-part1.html https://medium.com/@andkulikov/animate-all-the-things-transitions-in-android-914af5477d50 https://code.tutsplus.com/tutorials/introduction-to-the-new-lollipop-activity-transitions--cms-23711 https://developer.android.com/training/material/animations.html
http://gunhansancar.com/change-language-programmatically-in-android/ https://stackoverflow.com/questions/37454353/how-to-programmatically-change-language http://www.sureshjoshi.com/mobile/changing-android-locale-programmatically/ http://blog.nkdroidsolutions.com/change-language-programmatically-android-app-building-multi-language-supported-app/
https://stackoverflow.com/questions/5734678/custom-filtering-of-intent-chooser-based-on-installed-android-package-name https://stackoverflow.com/questions/13167583/clearing-and-setting-the-default-home-application/13239706#13239706 https://stackoverflow.com/questions/23322040/how-do-i-get-the-default-app-chooser-dialog-to-appear-even-if-the-default-app-is
http://gunhansancar.com/bottom-sheets-in-android/ http://www.truiton.com/2016/07/android-bottom-sheet-example/ http://www.androidauthority.com/bottom-sheets-707252/ http://www.hidroh.com/2016/06/17/bottom-sheet-everything/
https://github.com/codepath/android_guides/wiki/Handling-Scrolls-with-CoordinatorLayout https://github.com/chrisbanes/cheesesquare http://blog.mohitkanwal.com/blog/2015/03/07/styling-material-toolbar-in-android/ https://guides.codepath.com/android/Using-the-App-Toolbar https://stackoverflow.com/questions/36554879/how-to-apply-a-theme-to-an-android-toolbar
https://www.androidhive.info/2013/09/android-fullscreen-image-slider-with-swipe-and-pinch-zoom-gestures/ https://github.com/chrisbanes/PhotoView https://github.com/davemorrissey/subsampling-scale-image-view
https://futurestud.io/tutorials/retrofit-2-how-to-upload-files-to-server https://futurestud.io/tutorials/retrofit-2-how-to-upload-multiple-files-to-server
https://medium.com/google-developer-experts/android-strings-xml-things-to-remember-c155025bb8bb