Privacy mode: mask all amounts, reveal on hover or toggle

I would like a privacy mode that hides every monetary value in the app, so opening FinWise in public does not put my finances on display.

The situation is ordinary: checking a balance on a train, in a queue, in a cafe, or in an open-plan office. On a phone especially, anyone beside or behind me can read the screen. Right now the only way to avoid that is not to open the app.

How I would expect it to work:

• Masked by default on every app open, showing something like R•••••

• A single toggle in the header that reveals everything, and hides it again when tapped a second time, OR just tapping value acts as the toggle.
  

• Peek on hover for individual values on desktop, so a single figure can be checked without unmasking the whole screen.
  

• Optional persistence, so it either resets to hidden every launch or remembers the last state, user's choice. Resetting to hidden is the safer default.
  

Three implementation details that matter more than they sound, from having built this myself:

• Mask on first render, do not hide after render. If values are rendered and then masked client-side, they flash visible for a moment on every page load, which defeats the point precisely when someone is looking over your shoulder.
  

• Preserve layout width. If the mask is a different width from the number, the whole page reflows every time you reveal or hide, which looks broken and makes the toggle feel unusable. Rendering the real value in an invisible sizing element and cross-fading the mask over it keeps the layout perfectly still.
  

• Handle keyboard and screen readers. Hover-only peeking is unusable without a mouse, so the same reveal should trigger on focus, and the masked element should expose something like "hidden value" rather than reading the digits aloud.
  

A secondary benefit worth mentioning: it makes screenshots and screen sharing safe. If I ever need to send your support team a screenshot of a bug, or share my screen on a call, privacy mode means I can do that without redacting anything by hand.

I have implemented exactly this in my own finance dashboard, including the masked-first render and the zero-layout-shift approach, and it works well in practice.