At present, Data Roaming is not available on Ting Phones.
Usually this is not a problem, since wifi is available in most locations. But, there are times when one might need or want to use Data when roaming. Perhaps for an important email or just wanting to check out something online.
I would welcome the ability to do so, even if the cost was a premium. It could be offered in either a higher-paid block of Data, or similar to how texts are charged outside the US.