We are sorry to hear that some Iphone users may get some difficulties using the chatroom, we are working a good solution for that, however for now these users can use the suggested step below to be able to use the chatroom correctly.
Open the chatroom on your Iphone using Safari.
Hide the toolbar of your safari!
The chatroom now should be fully functional for you.
If you want to get your toolbar back, all you need to do is to click on the http link on the top