The reason for the delay of the "IRI Express" app for iOS is that Apple needs to approve the app before it can be installed in your device, and there is some bureaucracy involved with the approval process. There is a month or more turnaround time for Apple to look at the code and examine it vis-a-vis their own business model.
Especially, they may want at least a 50% local component along with a web component. Otherwise, they may reject the app since it threatens the lucrative app store business. Thereafter, they give approval, rejection, feedback for changes, etc. before making it available for install.
In...
more... the meanwhile, a Safari app/extension will be released soon which will provide some extra functionalities. Thanks for your interest.