On the app along the bottom you'll see all the different sections, subscribed is one of them, just press the tab and it will bring up all the threads you have subscribed to and the threads to look for will have a number in purple to the right of the thread, once you've looked at the thread the number will change to grey. When someone has added to a thread you're subscribed to it will register with a small red and white number above the subscribed tab.
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