You can do this from the browser on your phone. Granted this doesn't solve the 'in app' problem, but it does solve the clan issue. What I do to make this simple for people joining clans that I belong to is I log in to Bungie.net, go to groups, select the group in question, go to their main page / group wall, select the URL, email it to myself, open the email on my phone, copy the link and post it in a group forum withh e title 'clan tag.' People can then click on the link in the app and it will open as if in a browser. At the top of the page, below your clan name will be three options: Interact Set as clan About They can select 'set as Xbox clan' or whatever console you set. This way is a bit of a pain, but allows people to access your clan tag via the app.