CrossFlow
One keyboard, one cursor, every screen you own.
One keyboard and mouse drive several computers as if their screens were one continuous desktop — and a phone stands in as a trackpad and keyboard when there is no mouse to hand. Arrange your displays once; after that the cursor simply crosses the edge and typing follows it. The machine being controlled, never the sender, decides who holds input.
- 2Working today
- 6Being built
- 7Planned
The mechanism, not the metaphor.
- 01 Claim control
The source names a receiver and a layout, and gets back a generation and a controller lease.
- 02 Authorize
A crossflow.input grant binds that exact receiver and capability onto one authenticated channel.
- 03 Send frames
Key and pointer frames travel with their generation and sequence number.
- 04 Receiver checks
Peer, grant, generation, sequence and rate limits are all checked before anything is injected.
- 05 Inject, and remember
The platform adapter applies the event; the coordinator records every key and button now held.
- 06 Release everything
Escape, revoke and link loss funnel into one path that un-presses all injected state.
15 capabilities, and where each one stands.
Across desktops
- Planned Cursor crossing screen edges
Move the pointer off one machine's edge and onto the next.
- Planned Screen topology editor
Drag your machines' displays into the arrangement you actually sit at.
- Planned Generation-based ownership
Two computers cannot fight over your cursor; the newest claim wins cleanly.
- Planned Drag and drop across machines
Drag a file off one screen and drop it on another computer.
- Planned Clipboard handoff mid-flow
Copy on one machine, paste on the next, without thinking about it.
Your phone as the input device
- Being built Phone as trackpad
A high-precision trackpad with real pointer acceleration, at 240 Hz.
- Being built Phone as keyboard, real IME
Type Chinese, emoji and autocorrect using your phone's own keyboard.
- Being built Scroll, pinch-zoom, media keys
Scroll, zoom and change volume with the gestures you already use.
- Being built Edge sliders
Slide along the phone's edge to set brightness or volume.
Seeing and controlling a screen
- Working today Screen capture on macOS
Grab any screen or window through the operating system's own capture stack.
- Planned Screen projection
See another machine's desktop from anywhere you are signed in.
- Planned Control a headless box
A view grant plus a separate input grant equals full interactive control.
Safety, which is most of the design
- Being built Emergency stop
Three Escapes on the keyboard in front of you take control back instantly.
- Being built Link-loss release
A dropped link never leaves a key or a mouse button stuck down.
- Working today Two separate permissions
Granting screenshots does not grant control. They are different capabilities.
Numbers from tests that ran.
- 4.2 ms
Median gap between touch samples reaching the host at 240 Hz — against 17.0 ms over a 60 Hz browser path.
- 0.03 ms
p95 cost of the injection itself, once a frame has arrived and been validated.
- 8–14 pt
Per-frame cursor displacement, down from 26–55 pt. Smaller steps are what reads as smooth.
- 1.5 s
Dead-man release. Miss the heartbeat and everything held is let go, whatever the sender thinks.
And what it is not
- Not an unrestricted remote-control socket. The receiver holds authoritative state over who owns input and which keys it believes are held.
- The phone is not a second desktop. It allocates nothing, owns no cursor, and does not know where the pointer is — it sends deltas.
- Not an on-screen drawn keyboard. Thirty painted keys cannot type Chinese, swipe, autocorrect or emoji, so the phone's own keyboard is raised instead.
- Not one all-or-nothing permission. A machine with only Screen Recording gets a working capture tool and an honestly absent input capability.
Start with the devices you already own.
Make them work
as one.
The open core is ready to explore. Build your personal device fabric with Xross.
Open-source core · Direct by design · Your devices, your fabric