XTimer

Anyone who has run a conference session knows the problem. The speaker needs to see the clock, the person backstage needs to control it, and they're rarely on the same device. XTimer splits those jobs into links. One shows a fullscreen timer for the confidence monitor, one controls it, and others give a moderator view, a clean agenda page or a form where the audience can send questions.

Because it's all web pages, the controller can be a phone in the wings and the display can be any screen with a browser.

The run-of-show is what separates it from a basic countdown. You line up timed segments for the session, and they can start automatically on schedule. During a talk you can add time, push a message to the speaker's screen, such as a wrap-up cue, and have the display change color as it nears zero. Timers can count down, count up, show the clock or mix those.

The site also has a searchable set of free single-purpose timers for meetings, classrooms, HIIT workouts, Pomodoro focus and turn-taking games, which you can use without setting up a room.

The free plan covers the essentials with three connected devices and three timers, enough for a small meeting or a single talk. Pro, at $15 a month per seat, raises that to five devices and 50 timers and adds private outputs, API access and a custom logo. Premium, at $30 a month per seat, goes to 50 devices and 500 timers with custom theming. Both paid tiers have a three-day trial, and larger organizations can ask for an enterprise plan.