Remote control

During a Sessionwire call, you can control someone else's computer, once they click Allow. A recording engineer can run the session on the other person's computer, or fix a setting for them.

I've led development at Sessionwire since 2017. I designed and built the first version of remote control in August 2024, and reworked how it handles keys in 2026.

before

A call could already share a screen. The other person could see the problem, but only the person at that computer could click anything.

what changed

Allow: Nothing moves until the other person clicks Allow. While you're in control, a banner stays on top of their screen with a button to stop it. Since May 2026, you have an End Control button too.
Keys: Numbers, symbols and the number pad type what you pressed. From a Mac to a Windows PC, Shift and 1 to 0 type “!@#$%^&*()”.
Pointer: Up to about 60 moves a second, each one 19 bytes. The pointer lands on the same spot on their screen as on your view of it.
Tests: 55 automated tests on 8 October 2026, added from May to August 2026. The 2024 version had none.
Released: On the web on 10 September 2024, marked as a work in progress. Usable once the desktop app went out on 16 October 2024. It's still marked beta.

the decision

Keys and the pointer go directly between the two computers when the network allows it. Sessionwire's server only sets up the connection. When a firewall blocks the direct route, a relay passes them on.

A web page can't move a computer's real mouse. So the computer being controlled runs the Sessionwire desktop app. Since October 2024, the person in control needs it too.

Asking for control gets a pass from the server that works once and lasts five minutes. The other person still has to click Allow.

how it works

Each key and pointer move takes this path.

captureyour app, while your pointer is over their video
encodethe pointer as 19 bytes, numbers by their place on the keyboard
senddirectly to them, peer to peer, or through a relay
decodescaled to their screen by their desktop app
acttheir real mouse and keyboard, through nut.js

The detail: an ordered WebRTC data channel. The server passes the setup messages over Redis. Google's STUN servers find a direct route, and a TURN server relays when a firewall blocks one.

what went wrong

In August 2026, Shift and a number didn't work from a Mac to a Windows PC. Shift and 1 typed “1”, not “!”. The controller sent the symbol, and the part that presses keys on the other computer, nut.js, has no key for it.

Keys also stuck down on the other computer. If you let go of a key after your pointer left their video, the release never went out. On a Mac, holding Command hides the release of the letter, so Command and Z left the Z held down.

Now numbers and symbols are sent by their place on the keyboard, and Shift goes as its own key. A release goes out wherever your pointer is. Letting go of Command also lets go of the keys pressed with it. The fixes went out between 20 and 25 August 2026, in the web app and in desktop 2.8.0. That Mac and Windows pair is now checked by hand, with the exact characters each key has to type.

limits

Both people need the desktop app, on a Mac or Windows. You control the main screen only, and one person at a time. Keys are built around US keyboards. On another layout, a key can type the US character in the same place. Caps Lock, media keys and accent menus don't go through. There's no copy and paste between the two computers, and no dragging files across. No test runs a whole session from one computer to another.

Sessionwire: The product, year by year.
Call rebuild: How Call rebuild changed Sessionwire's calls in July 2026.
Triage: How Triage finds why something broke, and how I tested it.
Search: How Search finds people and music from a description.