how can we retrieve the publicly stored statements from Tin Can API?

Question

You can do a lot with the Tin Can API (Experience API). The point of the xAPI is to store user experiences, anything from I completed a course to I started watching a video. I've seen or worked on things as simple as using the xAPI to send SCORM tracking to an LRS, to support mobile, tracking sensor data from field exercises, to storing information collected in games and simulations. And the Experience API gives you the ability, like you said, to get data back out in a standard way, to support reporting and evaluation of data.

There are groups working with the Experience API to do interesting things. https://groups.google.com/a/adlnet.gov/forum/#!forum/xapi-design

There is also a spec working group forum where you can get more resources and answers: https://groups.google.com/a/adlnet.gov/forum/#!forum/xapi-spec

There are also resources and articles talking about what you can do with the Experience API. http://www.adlnet.gov/tla/experience-api/
and http://en.wikipedia.org/wiki/Tin_Can_API

There are some open source projects on ADL's GitHub page that also show how you can use the Experience API. https://github.com/adlnet

For sending and retrieving info from an LRS in web browsers there's a JavaScript library: https://github.com/adlnet/xAPIWrapper .. it's been built and minified..you can just include the xapiwrapper.min.js in your page and use the readme examples to get started.

For reporting and querying data you can look at the new project: https://github.com/adlnet/xAPI-Dashboard

There's a starting Java library to make talking to an LRS easier in Java, which could be used for regular Java apps or for Android apps: https://github.com/adlnet/jxapi

They're also starting a JQuery Mobile Plugin: https://github.com/adlnet/xapi-jqm

And even an example of using the Experience API with MedBiquitous and Common Core competencies to identify learner's progress toward becoming competent in some aspect: https://github.com/adlnet/xci

As for your question about getting statements from an LRS, you would just do a GET request to the statements endpoint. The spec currently says that requests must include the Experience API version header: https://github.com/adlnet/xAPI-Spec/blob/master/xAPI.md#62-api-versioning . And you will probably need to authenticate as a client using the LRS. This is generally done by registering on the LRS and getting some sort of credentials. This will vary based on the LRS you use, but they all have instructions on how to use and send the credentials. https://github.com/adlnet/xAPI-Spec/blob/master/xAPI.md#64-security

ADL's hosted example LRS opened up the GET statements endpoint so that people new to the Experience API could hit it and see statements without needing to figure out the request rules: https://lrs.adlnet.gov/xapi/statements