I am using XCode 6 and building the IPA. I have been following many posts in Stackoverflow and have gather information and the steps as to how to create the provisioning profiles and build the IPA.
I have been able to build the AdHoc IPA and have been successful in deploying it in my device. The application gets launched and is running fine. Now my query is that, as I am able to install the application on my device without any issues, does it mean that the IPA when uploaded to Apple will also get approved. (I am not using any private APIs. I am building my application using Appcelerator).
No, it doesn't mean that at all.
You've proven only the following:
Apple cares about a lot more than just that. For instance, you say it's "running fine", but Apple will test it fairly thoroughly to see if they can get it to crash. From personal experience, they might even find a crash that you can't replicate on your end (which is terribly frustrating!).
Also, Apple has gotten more picky about their approval process. I submitted an app that had an extra feature that linked to another app that was related but distinct. Apple ruled that my app was incomplete as it required another app to be fully-functional. What did I do? I removed the extra feature, and then Apple approved the app. Yes, I took away a feature and my app went from "incomplete" to "complete". My point? Apple's review process is fairly subjective and it can depend on who looks at your app and what kind of day they're having.
On your first app submission, be prepared for several back-and-forth sessions where they reject your app and you have something to fix. On the plus side, they're generally pretty specific about the problem they found, so it makes it easier to fix it!
You may get approved the first time out, but it's a higher bar you have to pass than just the items you mentioned in your post.
Also, you need to make sure that you have an appropriate Distribution profile. For loading to your device, you are most likely using a Development profile. Make sure you've gone through the steps to create an App Store Distribution Profile (which also required a Distribution Certificate, by the way).