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Web App runs inside Webview and installed like a native App

I created a Web App(PWA) via React and Bootstrap. It runs perfectly. I planned to create an Android and another iOS Apps that have only one page with a Webview that loads my Web App via URL and ship those Apps to the customer.
My question is that there is a better and standard way to this? I heard about Hybrid Frameworks like IONIC but as I understand, IONIC Apps, Are web Apps that run on device not loaded from a URL, Is that right?
What I want is that my changes in the server affect all users and Apps installed on their devices. Because of that, I created the PWA App, not the Native App. I searched a lot but I can't reach a final decision.
Used to be I was an Android developer and had a lot of problems with shipping the latest version to the customer, Now I want to use Web-based technologies to reach Apps that works like a website.

The issue here is: you will not be able to use the devices resources if you load the PWA in a Webview. For example push notifications will not work. A PWA can be installed onto a phone and windows as an application. This will have push notification on Android and Windows but not on Mac or iOS (Safari is the new IE). You need to go Hybrid or back to Native if you need more.
You are right with IONIC. It is a wrapper for a webapp stored on the device but it allows us to use native features (push works on both Android and iOS). But you still have the distribution issue since you need to publish to the stores every version. Not even mentioning the hoops apple gets you through when you try to publish.
The good thing with IONIC is you have a single source code for multiple platforms and you can choose the library you want to build with. It used to be Angular but now you can choose ReactJS, Vue, Angular or ES. Which makes it way friendlier.
With IONIC you could build the native features and lazy load the rest as dynamic component from a url: stackoverflow question if you do not care about backward compatibility.
I did both PWA and IONIC. Both has their pros and cons.
If I do not care about iOS and Apple I would stay with PWA otherwise IONIC.

using webrtc code on my cordova app

Im trying to use webRTC API such as getUserMedia and RTCPeerConnection for my app which is built with the cordova framework.
I am wondering if its possible for webRTC to work on both Android and iOS since my video chat app is a hybrid app (js and html) which is supposed to manage the entire p2p video chat by itself, unlike pc versions which require a web browser for the webRTC communication.

Yes, It is possible to get them to work. Keep in mind, the architecture of cordova application is reliant on a Web View rendering of your application. That web view will need to provide the WebRTC APIs to consume in JavaScript. This thread suggest the web view in iOS 11 does not support it. In fact, it is pretty new to Safari all together. This documentation says that the latest versions of Android Web Views do have support. WebRTC is a collection of technologies that enables RTC, and there are native libraries for accomplishing this. I have seen a couple of plugins for Cordova that enable access to native code so you are not as reliant on the Web View.
cordova-plugin-iosrtc
phonertc
Good luck!

Desktop native apps using web technologies

Are there any framework available that help to create cross platform desktop apps using web technologies ?
Couple of weeks back when I was surfing around tech blogs, I came across with framework doing the same and apparently Slack used it to create there desktop app from it. I am not able to find it again, I am not sure if it was TideSDK.

Got it. it http://electron.atom.io .It used by Microsoft, Facebook, Slack, and Docker for their application. Got the link from http://www.webappers.com/

Node.js app into an iOS app?

I have a Node.Js app running on a publicly accessible server.
I want to make it possible for users to access it as a native iOS app.
Is there a simple way of simply making an iOS app and having it show my Node.Js app running from the server? Or it's more complicated than that?
I looked into PhoneGap but maybe some other recommendations also?
Thanks!
PS I know the question is broad but that's why I'm asking – to focus my question and to know what to do next.

Node.js - this is a server side application. So you need to build client application which can communicate with your node.js server by Rest api or so...
As you mentioned you can build hybrid html5/js app with PhoneGap, Cordova, Ionic "wrappers/libraries" which will pack it into native iOS/Android/... application and that app can talk to your node.js server and transfer data you need.
Also, as Daniel Larsson mentioned for some specific pages you can use webview to display page straight from the web, but webview can be a part of your application but not an entire application, because Apple will reject it during review process.

If you want to port your existing web-app over to being a native app on the app store, I can positively recommend PhoneGap having developed multiple apps with it after completing the same research you are doing now.
As NYS said, you'll need to package all your web-app design (HTML/CSS+images/JS) inside the PhoneGap app, any other way simply wouldn't be responsive enough.
As for what to do next, I would dive straight into creating a PhoneGap application and see how your app runs inside the Cordova wrapper out of the box. The issues I faced were with scrolling on divs holding content, and non-responsive click events, both were easily solved with javascript libraries.
Cheers Chris!

You may use Socket.io for native option.
http://socket.io/blog/socket-io-on-ios/
https://github.com/socketio/socket.io-client-swift/
https://github.com/pkyeck/socket.IO-objc/
https://github.com/square/SocketRocket/

HTML5 Application (server or client side) using phonegap

I need to develop an HTML5 mobile business application using PhoneGap. After finishing my application I want to make it a native app.
Can anyone tell me What is the best way to do it
Develop an application using HTML5 and Javascript, call web services from Javascript and embed it in a native app using PhoneGap
Develop an application using HTML5, Javascript and PHP. (server side). use PHP to call web services. use PhoneGap to call server urls.
1st one seems more native and fast. 2nd one seems more flexible and secure, but I need an additional server for that.
so what is the best solution?

Although I agree this is too wide a question, I would go with #1 because certainly in the case of Apple and iOS I am pretty sure you would not be able to get an app past Apple's gatekeepers if it loaded remote code (Javascript, etc).
Calling out to a web service for remote data via AJAX, etc is fine however.