For this milestone add your Fiki the following:

1. Perform at least 3 face-to-face interviews with potential users (from your main targeted customer segment)
2. Create a user persona (or the main user persona in case of targeting multiple customer segments)
3. User stories, use cases / user flows
4. Update your wireframes to reflect the findings uncovered by this milestone

Don't forget to document everything regarding the interviews and highlight the conclusions from on your findings.