Google recently announced a tool at the Google I/O conference called Domain Test. Domain Test is a way for developers to test if their applications are compatible with the new top-level (TLD) domains that are currently being released. The Domain Test product was launched as a partnership between Google Registry, Donuts, Uniregistry, and Ausregistry as an open source project available under the Apache 2 license, and is currently available to be used for free on 126 New TLDs.
Domain Test is a powerful resource for developers because the New TLDs contain new domain aspects such as long lengths and non-Latin characters that can cause software bugs. The tool is currently available on Github and the repository is filled with documentation and code for Domain Test so that developers can easily find and fix problems.
The service runs on AppEngine and any developer can use it. You can head over to GitHub and use Domain Test here.