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Our users were friends from our living groups who had varying levels of interest in music. While they're all MIT course 6 students and so might not be generally representative, MIT students seem to have a pretty wide range of musical inclination and so weren't a particularly bad sampling of our user population, though they might have been more familiar with the inner workings of programming than most most of them were programmers (don't think any of them had programmed on Android before, though). Our app aims to be usable by people with varying levels of music experience and who are probably somewhat younger, creative and tech-savvy enough to carry a smart phone.
We conducted user tasks by telling the user the purpose of the app (record songs without having to figure out the musical notation and when you're on the go) and the target audience (should be usable by people without a lot of musical experience).
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We had two editing interfaces that we can't decide between. We tested this by having different users test different editing interfaces first, give us their comments on it, then switch and give us their comments on the other one. I should've been careful to not tell users who made which interface, but I think I failed at this for the first two.
We tried to stay silent during observation, only giving tasks, then at the end asking questions about certain things the user did that they didn't explain, or things they may not have discovered.
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