Hall Clock

Hall Clock is the phone controller for a meeting timer that runs on a small
appliance in your hall and shows the time on the hall's display.

Start and stop the timer, move to the next item, adjust the running time by a
minute, jump to any item in the schedule, and see how the meeting is tracking
against its planned finish — all from your phone, without leaving your seat.

REQUIRES A HALL CLOCK DEVICE

This app is a controller only. It connects to a Hall Clock appliance on the same
local network as your phone, and has no function without one. There is no online
service, no account to create, and nothing to sign in to.

WHY AN APP AND NOT JUST THE BROWSER

The controller is a web page served by the appliance, so it already works in any
browser on the same network. This app exists for the two things a browser cannot
do with a plain local-network page: open full screen with no address bar, and
hold the screen awake for the length of a meeting so the timer stays visible
without anyone touching the phone.

CONNECTING

The app opens your hall's clock automatically. If your hall uses a different
address, tap Change address and enter it once — it is remembered from then on.

PRIVACY

No accounts, no analytics, and no data leaves your local network. The app
communicates only with the clock appliance on your own network.

The "REQUIRES A HALL CLOCK DEVICE" section is doing double duty — it sets user expectations and it's the thing a reviewer reads when the app shows only an error screen on their test device. Keep it prominent, and put the same explanation in the App access field.