The Invisible Screen – An E-Paper Smart Display

Original Article ↗ Hacker News Discussion ↗

An e‑paper wall calendar called the Invisible Screen is drawing interest as a minimalist, low-glow way to show daily schedules, but many potential buyers question its small 7.5" size, closed ecosystem, and reliance on a remote backend that could turn it into e‑waste. Commenters compare it with DIY solutions using Kindles, Raspberry Pis, or Waveshare/Inkplate panels, arguing that hackability, local control, and open APIs are more important than plug‑and‑play convenience. The exchange also highlights broader frustrations with e‑ink pricing and the lack of large, affordable, open e‑ink displays for home dashboards and “calm” information radiators.

Form factor & screen size

  • Screen is 7.5" at 800×480; several readers expected something closer to 15" based on product photos.
  • Suggestions to add size references (keys, banana, etc.) to avoid misleading impressions.
  • Some feel 7.5" is fine for a day view but too small for week views or a “command center” display.

Price vs DIY and alternative hardware

  • Many note you can buy Waveshare panels (including larger 13.3") or reuse e-readers/Kindles for similar or lower cost, but that requires hardware work and coding.
  • Some view this product as fairly priced for a polished, plug‑and‑play package; others call it expensive for a “novelty” given Kindle/cheap tablet specs and subsidies.
  • A few mention Inkplate and similar boards as more open but requiring enclosures and programming.

Openness, backend dependence & longevity

  • Device is closed source and depends on the vendor’s backend, including for custom content (proxied image URLs).
  • Several worry about e‑waste if the company or servers disappear; some say they would pay more for local‑only, flashable hardware.
  • The maker says local‑only mode is technically possible but nontrivial; states an intention to keep the backend running for 10 years after the last sale, but acknowledges that’s only a plan.

APIs, calendar support & integrations

  • “SDK” is effectively an image URL API: users can serve any bitmap and the device displays it.
  • Calendar support currently focuses on Google Calendar and generic .ics feeds; multiple calendars and .ics are supported.
  • Outlook/Office 365 integration is widely requested; it’s said to be on the roadmap.
  • Users debate the assumption that everyone uses Google; many home users do, but office users often rely on O365 with tricky API approval.

Power, battery & refresh

  • Lack of a battery is a common complaint; wall power limits placement and adds cable clutter.
  • DIYers report battery‑powered e‑ink dashboards lasting months with infrequent updates.
  • Device fetches updated images roughly within 1–2 minutes of a changed URL.

Use cases & reception

  • Reported uses include household daily schedule boards and custom dashboards.
  • Several buyers say setup is easy and the product “just works.”
  • Wishlist items: larger sizes, touchscreen, voice control, offline mode, richer integrations (Home Assistant, smart home, news, etc.).