We have been discussing doing this for some time. The Hackathon would be an ideal situation to create a spike that would be valuable into the future.
Our current thinking is to use Appium and SauceLabs for this work.
At various time we have reviewed mobile test frameworks, and Appium seems to be both well supported and also the best fit for our existing UI test framework.
There are also platform-specific "integration test" frameworks that might be worth exploring: