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When discussing secure communication that also hides who you’re talking to, he stated that cloaking who you’re talking to would be a big benefit. It prevents leaking who you associate with, which can give away a lot of information.
TA Feedback.
This is a good start, but there are some big things missing. You don't actually discuss classes of users, just specific interviewees. Your task analysis doesn't seem to be much connected to those interviews, either. For instance, where do public conversations come in? They aren't mentioned anywhere in your user analysis, yet you say that it's a 'semi-often' action.
You also don't seem to really get a good feel for what the tasks your users use to solve your problems, and instead you describe actions that your app will let users take. Don't forget that the next step is to make three separate designs - you shouldn't already have picked one. Think of task analysis as the analysis of tasks that need to be done to solve the problems.
I'd appreciate it if you made these changes, since we'll be working off this document for the whole rest of the project.