Linking multiple social accounts in one app

Before I get started, I know that the scope of the questions may be too broad, but I think the discussion of strategies is appropriate for this site.

However, I would like to create a mobile application that pulls data from different social networks.

This of course requires that I be able to log into every service and have an API / library that works with my platform, which is Windows Phone 8.1, unless everything is done online with some service.

I am thinking how to get everything to work and I came up with two ideas:

• Import and use the .NET library / wrapper to connect and work with the service directly on the user device.
• Create an Azure Mobile Service that allows users to create an account for my application and associate it with each of their social networks, work with services on the Internet, and make their application only with my AMS.

This is the current situation for social media that I would like to use:

+----------------+---------------------------------+--------------------------------------------------------------------+
| Social Network |          Windows Phone          |                               Azure                                |
+----------------+---------------------------------+--------------------------------------------------------------------+
| Facebook       | http://facebooksdk.net/         | login supported                                                    |
| Twitter        | http://tweetinvi.codeplex.com/  | login supported                                                    |
| Instagram      | http://instasharp.org/          | not supported                                                      |
| Foursquare     | SharpSquare can be adapted      | https://gist.github.com/rfaisal/9899185#file-login-js may work (?) |
| Flickr         | https://flickrnet.codeplex.com/ | not supported                                                      |
+----------------+---------------------------------+--------------------------------------------------------------------+

      

        
        
        
      

    

Now that Windows Phone seems to be the best it will force me to deal with different login workflows and can cause problems if the APIs of one of the services change because I will need to update the application and make it work with the new APIs, assuming that the developers behind these libraries decide to update them as well!

Using Azure will only require one server-side update, which makes it easier to manage and also helps manage heterogeneous user data because I can parse it online and I can return it in a format that is common to all services (bandwidth reduction, used by the device to download the useless stuff included in the service APIs).

I also looked into something else and I found Auth0 which seems like a good service, but they don't support Foursquare / Flickr and the free account is too limited.

Another cool service I found is https://intridea.github.io/omniauth/

To be honest, I have a lot of doubts about how I thought, and this brings us to the real question:

Given that all the services I want to use are based on oAuth2 + REST APIs, how would you make this work? Is everything that has been done on the server side better, or is it okay to make the same application on every server right on the device? Regardless of your choice, how would you store user logins?

Since this question is open to many different answers, I'll answer every helpful answer, and I'll agree that gives me an easier script to work with.