Develop Reference

What is the Difference between Xamarin and Telerik Platform

This is going to be quite a hectic question and im hoping that you can all Bear with me.
Im having difficulty fully understanding some things about mobile App development.
So my Main question is : What is the difference between Telerik Platform and Xamarin ? Dose it just depending on what you are more comestible with, Like if you are a c# developer and know the .Net framwork, Then use Xamarin or is it alot more complex than that ? As i know that Telerik uses Javascript, so is it more of an open dev based mobile app ?
Which is better for the future of mobile development as i want to move in the right direction.
As an Extra: Has anyone heard of Dart ? i found out about it last week and haven't had much time to Read up on it, but it looks like a web based solution from google.
Dartlang

In Xamarin you can build native applications for Android and iOS system.
It is also possible to write them for Windows Phone.
Xamarin uses C# language.
Apps are created natively using Xamarin wrappers.
There are two options for creating apps in Xamarin:
1) Xamarin.Forms is best for:
Data entry apps
Prototypes and proofs-of-concept
Apps that require little platform-specific functionality
Apps where code sharing is more important than custom UI
2) Xamarin.iOS & Xamarin.Android are best for:
Apps that require specialized interactions
Apps with highly polished design
Apps that use many platform-specific APIs
Apps where custom UI is more important than code sharing
Telerik Platform is good for web developers who want to create mobile apps:
Here you can write html and javascript.
Remember also that your apps on iOS and Android will be displayed in WebView (browser). Only Windows Phone apps can be written in html and javascript natively.
Hope this will help.
Please also see this (I asked about Xamarin and Apache Cordova):
http://www.codeproject.com/Forums/13695/Mobile.aspx

All of the mentioned framework do the same thing in different ways, its totally depends upon your skillset and interest which framework you find easy to understand or find interesting.
Each of those have their market in which you can grow. below are some links may help you.
http://www.telerik.com/campaigns/build-mobile-apps-with-dotnet
https://forums.xamarin.com/discussion/13686/the-future-benefits-of-xamarin-over-other-options-and-mobile-apps-replacing-websites

Dart is a modern open source programming language that allows to write concise code
built-in support for async/await, Future (Promise), Stream (Observable), ...
Supports lots of platforms
Server with the Dart-VM (Windows, OSX, Linux)
in the browser after to-JS transpilation
Android and iOS by Flutter https://flutter.io/
embedded systems by Dartino https://dartino.org/
Dart can be transpiled to JavaScript (to-TypeScript is work in progress)
extensive high-quality standard libraries
dart:html library that for browser abstraction that makes most polyfills redundant
shipped with lots of tools
package manager
analyzer/linter
debugger and profiling tools
test runner
Dartium development browser
...
IDE support
easy integration using the IDE services the analyzer provides
Atom plugin
WebStorm/IntelliJ plugin
...

Implement otr.js in titanium appcelator ios?

I'm trying to create a chat application using Titanium appcelerator for iOS. For that i have implemented OTR.JS in my node js application. That works fine, But now i want to implement OTR.JS in Titanium Appcelator.
I searching modules in Titanium Appcelator to implement OTR for my application. But I can't found any solution for this.
So can anyone clarify me, To use OTR.JS in my Titanium Appcelator Application. If there is any example, please suggest me.

The only Titanium module implementing OTR supports only Android platform: https://github.com/mnaamani/titanium_otr
However you can try using plain JavaScript implementation like this one: https://github.com/arlolra/otr

Is it possible to implement HTML5 (I plan to use WebRTC)as a WebView within a native Android application?

I am thinking about developing a android application to make a WebRTC call. Unfortunately the native WebView in android does not support such feature. I tried XDK with CrossWalk and it works with WebRTC well, but the problem is that it is a pure HTML, Javascript application. I suppose the capability of HTML5 application in android would be a problem? (Notification, service, communication with database). So what I am thinking is that maybe I can build a hybrid application with the framework of a native application and a WebView with it? Thanks in advance, that would help me a lot.

Yes, it is possible. I build this HTML5 , https://www.noupei.com/. Its fully HTML5, build using jQuery and jQuery Mobile. One of my college easily transpose it using a webview for android, https://play.google.com/store/apps/details?id=com.knowledge7.android.noupei
BUT
It is also possible to completely develop your whole application using HTML5, and then package it with something like phonegap, the advantage you have is that using something like phonegap allows you to access the native features of the Android Device.
For HTML5 technologies like Bootstrap that allows you to make very good mobile interfaces are fully mobile responsive. It is possible to make very beautiful and attractive interfaces as well as you also have very good javascript frameworks like AngularJS.

Writing apps for Apple platforms with Javascript

Does Apple allow iOS and Mac apps to use Javascript? Can someone give me examples of how to use it and the advantages and disadvantages?

If you're looking for a less techy solution, you could also use AppFurnace ( http://www.appfurnace.com ) to create JavaScript & HTML5 apps, packaged as native apps for iPhone and Android. We use PhoneGap (mentioned above), with an added drag-and-drop interface, enabling you to make your own apps.

You can use phonegap as a javascript, html and css wrapper in your ios app if you want to create a native app using html and javascript.

There's NimbleKit which allows you to make native apps using HTML and Javascript. Otherwise you can use a UIWebview which you can execute Javascript in. Look at the UIWebView documentation for more info.

There are tools to code your app in javascript and compile it into native code.
But if you want your app to load javascript code at runtime and run it, then see this for more details.

Javascript app in Android

I am new to Android programming, and looking for some general knowledge. I am considering writing logic of my application in javascript so that the same code could be executed in a webapp and in a desktop application. Would it be possible to also have it working on Android? I know that:
SL4A is marked as alpha-quality, and user would need to install it to make such an app work. Still it provides access to Android API. SL4A scripts also cannot go to Android Market, as far as I know.
A simple webapp doesn't have access to most Android API.
Would it be possible to write a simple Java app that would embed an HTML widget with javascript code and provide some wrapper to access necessary API?
I am not looking for a fully portable thing--I intend to adapt UI to each environment manually. I just would like to have the internal logic common to all ports.

PhoneGap allows you to write an HTML-based app that not only works with Android, but also iPhone, Windows Phone 7, WebOS and more. The API is standardized, so you can use the same page on all the platforms.
There's support for the most common native features on most platforms. (Here's a chart of the features supported on each platform) In addition, if you find that there's a feature you cannot replicate using only their API, you can write a plugin in the native platform language (so, for Android that'd be Java), and then call that plugin from your HTML/Javascript-page.

If you want to use javascript and access the native api then you should try Appcelerator.com. Those people are providing this.

There is Rhino, which is a Javascript engine written in Java. It works in Android, and it is used by Appcelerator's Titanium mentioned in another answer here.
User interface and Android-specific API can then be written and wrapped in Java, then called by the logic code written in Javascript and run by Rhino.

Consider GWT, a Java to javaScript compiler. You can write your logic and a lot of other code in plain old Java(There are a few things(e.g. reflection) that you can't do like reflection but you wouldn't be able to do it in javaScipt either) Applications like Google inbox are using GWT to reuse a lot of their code in javaScript. They don't just reuse logic either. You can reuse dependency injection, your architecture, AJAX calls and more. Also, GWT is faster than javaScript in both the browser and the JVM. The biggest problem you might have with GWT is that it's more complicated javaScript. Regular Java is already more complicated. Making it work on both the JVM and browser can only make things more complicated. Also, GWT was designed from the ground up for extremely complciated web apps.