Second Monitor Guide

Turn a spare phone or tablet into a second screen

Second Monitor Guide — turn a spare phone or tablet into a second screen with setup steps, bandwidth, latency estimates.

How to use Second Monitor Guide

  1. Install the same virtual-display app on both the host computer and the spare device, and sign in or pair them if the app asks.
  2. Connect the spare device to the host with a data cable (not a charge-only cable). On a phone or tablet, allow the computer when the trust prompt appears.
  3. In the app on the host, choose the wired / USB connection option and pick the spare device when it appears.
  4. On the host, open the display settings and confirm the spare device is set as an extended display, not a mirrored one.
  5. Arrange the displays in the host display settings so the spare screen sits where it physically sits (left, right, above or below).
  6. Open a window, drag it onto the spare screen, and check text is sharp. If it is blurry, lower the resolution or raise the quality setting in the app.

Features

  • Pick host device (Mac / Windows / Linux) and spare device (iPad, iPhone, Android tablet, Android phone, old laptop)
  • USB vs Wi-Fi setup guides
  • Bandwidth calculator (resolution 720p–4K, refresh 30/60/120 Hz, colour depth 24/30-bit, codec raw / H.264 high / balanced / heavy)
  • Latency estimator per connection (USB 3.0, USB 2.0, Wi-Fi 5 GHz, Wi-Fi 2.4 GHz)
  • USB vs Wi-Fi comparison table with fit/over-capacity verdicts
  • 6 troubleshooting entries
  • Rotating tips
  • Copyable estimate summary
  • Every figure labelled estimated

Frequently asked questions

Is it free?

Yes, unlimited.

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