Develop Reference

Twilio video with Flutter

We are planning to integrate Twilio video SDKs for video conferencing in our existing application which is in Flutter. From the documentation of Twilio SDKs it is pretty sure that it is just for native Android development and not for frameworks like Flutter. So how can I to use Twilio video SDKs in my mobile app development (Android and iOS)?
Is it possible to create UI in both native Android and the framework (Flutter) at the same time within same application?
Is it technically possible and if yes, how to do it?

There is a existing Twilio Video Flutter plugin already hosted on pub.dev. The repository can be found here.

How to build a simple Native WebRTC Android application that can do basic video call?

Recently I've been struggling a lot with WebRTC, I was able to build a very simple WebRTC web application based on the WebRTC codelab which consists of a simple signaling server (basically step 8 in the codelab tutorial).
My next target is to build a native Android application that does the same thing which is to be able to make video call with the web application using the same simple signaling server. I am very new to WebRTC and I could not find any good tutorial or guide that allows me to build a simple native Android application.
I've searched for similar questions on Stackoverflow but most of them are outdated and do not provide useful answers that I need.
I'm hoping the Stackoverflow community who knows any good source or tutorial on how to build a simple and basic native WebRTC Android application can share with me their knowledge and information. Thank you so much.

I suggest you build the AppRTCMobile target in WebRTC (see https://webrtc.org/native-code/android for details on how to build etc) then deploy your own instance of AppRTC (https://github.com/webrtc/apprtc) if you wan to have full control over the signaling. Otherwise you can just use the one publicly available at https://appr.tc.

using webrtc for hybrid app

We are working on an app Which requires Video Chat functionality. Is it possible to use hybrid and webrtc or any other lib to support IOS and Android?.
I have seen a few post with similar queries but those are year an old so any new Update on it.

I use the Cordova plugin iosrtc : https://github.com/eface2face/cordova-plugin-iosrtc
If that can help you, I create a sample application that creates a webrtc call on iOS : https://github.com/apizee/ApiRTC-mobile
I will finish the android version soon.

I used Skylink which is cross platform (iOS, Android and web), works well for me.
EDIT: As of 2020 I would explore more options.

Custom WebRTC SDK for Android

I am trying to develop my own sdk webrtc for android based on WebRTC.
I have my own signalling server and STUN/TURN server.
I need pointers on how to start to develop the sdk which the third party developers will use to develop their apps using my sdk.
Currently, I am exploring the WebRTC sdk and the demo app for android.
Mine specific questions are:
How would I provide the SO(libjingle_peerconnectcion_so.so) and JAR(my own java implementation for signalling and STUN/TURN and other app specific things) files together as one JAR file?
Is there any other alternative for the above said scenario?
Any help/resources are welcome.
Regards

Maybe you could check these projects whose aim is to provide a cordova plugin for WebRTC (both for iOS and Android):
https://github.com/alongubkin/phonertc
https://github.com/remotium/cordova-plugin-webrtc

Is it possible to build a native android-to-android video chat app using webrtc?

I see a lot of tutorials in the Internet teaching about android to browser or browser to browser webrtc application. Is it possible to build a native android-to-android video chat app using webrtc?

Well, for establishing a connection between the devices before the call via peer-to-peer WebRTC solution you need STUN/TURN/ICE servers.
They establish the route for communication between the devices.
Once the route is established the devices communicate directly without participation of a server for passing the media streams.
To make it easier for you, you can look at or try some existing solutions, like ConnectyCube.
They have peer-to-peer WebRTC solution for Android already implemented.
So, maybe there is not need to reinvent the wheel.

There is an official Android sample project AppRTCMobile provided here - https://webrtc.org/native-code/android/. However, the build process is tedious and the total download size exceeds 20 GB. The recommended way is to use the following dependency in your project.
implementation 'org.webrtc:google-webrtc:1.0.+'
However, for video chat functionality you will need to refer AppRTCMobile source code. There is a clone of this project on GitHub updated for Oreo and ready to import in Android Studio. Check out this link.

WebRTC uses ICE protocol for creating connection between two peers. It uses DTLS-SRTP for creating secure data exchange between peers.
Now both ICE protocol and DTLS-SRTP are protocols that can be implemented on any devices no matter what platform. You implement or use existing implementation of
ICE and DTLS-SRTP protocol on your android apps and communicate with each other.
When you read tutorials about implementation of WebRTC for communication between android app and browser, there the android app has the implementation of both ICE and DTLS-SRTP. So this android app can communicate with other android app having similar implementation.

in addition to #tahlil great answer, you can also use a number of open source SDKs out there that already took the burden on bundling the WebRTC libraries and offering simple APIs for you to integrate Real Time Communications in your native app. One example of such SDK is the RestComm Android SDK
See https://github.com/Mobicents/restcomm-android-sdk and http://www.telestax.com/restcomm-client-android-sdk-beta-2-is-out/