Multi-Device Counter
Synchronize totals across connected devices.
Tap, click or press Space to keep count.
Tap anywhere inside or press Space
How the Multi-Device Counter Works
The Multi-Device Counter keeps one counter in sync across phones, tablets and computers, so a tap on any connected device updates the total on all of them.
- Create a synced counter: Start a counter and generate a link or QR code.
- Connect devices: Open the link or scan the code on each device.
- Count on any device: Taps from any device add to the same total.
- Watch the sync status: A status dot shows whether each device is online and up to date.
Multi-Device Counter Formula
The Multi-Device Counter synced total equals the sum of increments sent from every connected device. Sync delay equals the time a change takes to appear on another device.
- Increments(d)
- Changes sent by device d
- t_sent
- Time a change left the device
- t_received
- Time another device showed the change
Example: A phone adds 30, a tablet adds 45 and a laptop adds 25. Total = 100 on all 3 devices. A change sent at 0 ms and shown at 180 ms has a sync delay of 180 ms.
Multi-Device Counter Reference Table
The Multi-Device Counter conversion table lists typical sync delays by connection type.
| Connection | Typical sync delay (ms) | Typical sync delay (s) | Counting impact |
|---|---|---|---|
| Same Wi-Fi network | 50 to 150 | 0.05 to 0.15 | Instant |
| 5G mobile | 50 to 200 | 0.05 to 0.2 | Instant |
| 4G mobile | 100 to 300 | 0.1 to 0.3 | Near instant |
| 3G or weak signal | 500 to 2,000 | 0.5 to 2 | Visible lag |
| Offline | Queued until reconnect | — | Syncs later |
About the Multi-Device Counter
A Multi-Device Counter is a counter whose total is shared live between several connected devices. Each device sends increments, not totals, so 2 people tapping at the same moment never overwrite each other.
Sending increments is how distributed counters avoid lost updates. A device that goes offline queues its taps and sends them on reconnect, so the final total stays correct.
Ways to Use the Multi-Device Counter
The Multi-Device Counter has 5 main uses, including multi-door counting and a display screen.
- Multi-door counting: Staff at 3 doors update one occupancy number.
- Display screens: A laptop shows the live total on a projector while phones count.
- Personal sync: Users count on a phone and check totals on a tablet.
- Classroom tallies: Teachers count on a phone while the board shows results.
- Event dashboards: Managers watch live counts from a back office.
Tool Details
- Category
- Tally & Calculation
- Controls
- Taps and keys
- Input Support
- Touch, Pen, Mouse, Keys
- Offline Ready
- On your device