Every phone has a timer. Most labs still end up with a drawer of cheap plastic ones, which tells you something: the phone timer is not failing because it cannot count down. It is failing at everything around the counting.
Labels, or it is just a number
The first requirement is that each timer carries a name. Three unlabelled countdowns are worse than one, because when the first alarm sounds you now have to work out which of the three it was, and the answer is not on the screen.
This sounds trivial until you are running a wash series, a block and a development step at once. The label is what makes the alarm actionable instead of merely loud.
Genuinely concurrent, not queued
A surprising number of timer apps let you set several countdowns but only run one at a time, or reset the running one when you start another. Test this before you trust it: start two, watch both, and start a third while the first two are running.
Alarms that survive the screen locking
The failure mode that costs real experiments is the timer that stops when the tab is backgrounded or the phone locks. On a bench that is exactly what happens — you set it down, it sleeps, and the alarm never comes. Any timer you intend to rely on has to be tested this way once, deliberately, on the device you will actually use.
Restarting a repeated step in one action
Wash steps are the same duration over and over. If restarting means retyping the duration, the timer will be abandoned by the third repeat. A one-tap restart is the difference between a tool that is used and a tool that is installed.
What is worth less than it looks
- Elaborate sounds — you need one alarm you can hear over a fume hood, not twelve you cannot tell apart
- Colour themes, unless the colour is carrying information such as which sample a timer belongs to
- Cloud sync of the timers themselves — a countdown is not useful on another device thirty seconds later; the protocol behind it is
- Step-by-step protocol automation, which sounds ideal and in practice fails the first time a step runs long
The honest summary
A good lab multi-timer does four things: several countdowns at once, each with a name, an alarm that fires with the screen off, and a one-tap restart. Everything beyond that is preference. Anything missing from that list will eventually cost you a run.