Mobile App Resources
Flutter & Ionic
V-Play Engine
https://v-play.net/
NativeScript
https://www.nativescript.org/nativescript-sidekick
https://market.nativescript.org/plugins/nativescript-aws-sdk
https://github.com/triniwiz/nativescript-aws-sdk
https://github.com/EddyVerbruggen/nativescript-nodeify
React Native
https://github.com/Microsoft/TypeScript-React-Native-Starter
Essential cross-platform UI components for React Native
https://github.com/ipselon/structor/blob/master/docs/designing-ui.md#designing-ui
Cordova
https://github.com/masahirosuzuka/cordova.swift
plugman create --name ModusEchoSwift --plugin_id com-moduscreate-plugins-echoswift —plugin_version 0.0.1 --path modusechopluginswift
https://github.com/nraboy/ngx-cordova-oauth
https://moduscreate.com/writing-a-cordova-plugin-in-swift-for-ios/
iOS
https://eezytutorials.com/ios/nsnotificationcenter-by-example.php
https://developer.apple.com/library/content/documentation/IDEs/Conceptual/AppDistributionGuide/TestingYouriOSApp/TestingYouriOSApp.html
https://developer.apple.com/documentation/avfoundation/avaudioplayer
https://developer.apple.com/documentation/mediaplayer
https://developer.apple.com/documentation/mediaplayer/mpnowplayinginfocenter [info center]
https://stackoverflow.com/questions/44382841/how-do-you-perform-wireless-debugging-in-xcode-9-with-ios-11-apple-tv-4k-etc
https://help.apple.com/xcode/mac/9.0/index.html?localePath=en.lproj#/devbc48d1bad
https://developer.apple.com/library/content/referencelibrary/GettingStarted/DevelopiOSAppsSwift/BuildABasicUI.html#//apple_ref/doc/uid/TP40015214-CH5-SW1
http://pulkitgoyal.in/ios-music-player-on-the-lock-screen/
https://www.appcoda.com/ios-avfoundation-framework-tutorial/
https://www.hackingwithswift.com/example-code/media/how-to-play-sounds-using-avaudioplayer
http://www.justindoan.com/tutorials/2016/7/31/mpmedia-tutorial-control-music-playback-in-ios-with-swift
https://objectivec2swift.com/#/converter/
https://github.com/lukagabric/LGAudioPlayerLockScreen
https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/StoreKitGuide/Introduction.html#//apple_ref/doc/uid/TP40008267-CH1-SW1
https://developer.apple.com/library/content/documentation/LanguagesUtilities/Conceptual/iTunesConnectInAppPurchase_Guide/Chapters/Introduction.html#//apple_ref/doc/uid/TP40013727-CH1-SW1
https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/StoreKitGuide/Chapters/Subscriptions.html
https://developer.apple.com/support/apple-pay-sandbox/
https://adapty.io/blog/how-to-test-ios-in-app-purchases/
https://developer.apple.com/documentation/appstoreserverapi
https://developer.apple.com/documentation/storekit/in-app_purchase/original_api_for_in-app_purchase/fetching_product_information_from_the_app_store
https://www.miradore.com/knowledge/ios/adding-ios-devices-to-apple-business-manager-with-apple-configurator-2/
Manually add devices into Apple Business Manager using the Apple Configurator App
Android
https://developer.android.com/google/play/billing/billing_subscriptions.html
https://developer.android.com/google/play/developer-api.html#subscriptions_api_overview
https://developers.google.com/android-publisher/api-ref/purchases/subscriptions#resource
keytool -export -rfc -keystore upload.keystore -alias uploadkey -file upload_certificate.pem
keytool -v -list -keystore /path/to/keystore
Chat
https://dashboard.applozic.com/ (almost free, seems the best) [ios,android,js,phonegap,ionic,xamarin,api]
https://sendbird.com/ (free) [ios,android,js,unity,.net,api]
https://quickblox.com/ (free) [ios,android,js,api]
https://chatsdk.co/ (totally free) [ios, android]
Various
https://material.io/devices/
https://softwareengineering.stackexchange.com/questions/206310/data-synchronization-in-mobile-apps-multiple-devices-multiple-users