If the TV has a web browser, or an Apple TV, or an HDMI port, you already have what you need. Here are four ways to get a workout timer on the big screen, with what each one costs you.
Nothing is installed on the TV and nothing is cast. Every screen is timed by the server rather than by your phone, so the TV and phones stay within a fraction of a second of each other, and it reconnects on its own if the Wi-Fi blinks. The free tier allows 5 viewers; ClockKeepers Pro ($7.99 once) removes the cap.
Some smart-TV browsers are slow or missing entirely. If yours is awkward to type on, use the QR code or one of the options below.
If you have an Apple TV, or a USB-C to HDMI adapter, ClockKeepers' Present mode shows the clock full screen on the connected display with no link or code. It works without broadcasting at all, but only one screen shows it and your phone has to stay connected.
Some timer apps cast to a TV with Chromecast, for example SmartWOD Timer, per its App Store text. That works, but you need the hardware plugged into the TV and the app on the casting phone. If you already own one, it is a fine choice; if you do not, you can skip buying it. See ClockKeepers vs SmartWOD for the full comparison.
Plug a laptop into the TV by HDMI and open the ClockKeepers web app in a browser, then control it from your phone through Broadcast. This is the most reliable setup for a gym with an old TV and no smart features.
No. If the TV has a web browser, open the ClockKeepers web app and type the 5-letter code. If it does not, use AirPlay to an Apple TV or an HDMI adapter.
No. Nothing installs on the TV. It only needs a web browser.
Up to 5 screens follow free; unlimited viewers with ClockKeepers Pro.
As a single-device timer, yes. Broadcasting to other screens needs an internet connection.
One timer and five viewers free, no account, no ads. ClockKeepers Pro is $7.99 once.
ClockKeepers