On iPhone, I noticed that concerning the icon for public/private personnal info fields:
- on the User Profile page, you get a tooltip when you touch the icon ("Private" or "Visible to everybody").
- on the topic edition window, you can't get the tooltip when you touch the same icon.
- on the window claiming to complete your profile before submitting a feedback, you can't get the tooltip when you touch the same icon.
=> the tooltip would be useful in the last two cases as it is available in the 1st case.