Controller and networking guides tend to use a lot of shorthand. This glossary explains the terms that come up when you use a phone as a PC controller, in plain language and with a pointer to the guide that goes deeper. It is organised alphabetically in four groups, so you can scan for the word you just ran into.
A to D
ABXY. The four face buttons on an Xbox-style controller, labelled A, B, X and Y, arranged in a diamond under the right thumb. In the GamepadOS layout builder they come as one cluster that you can move and resize. See the layout builder guide.
Analog stick (thumbstick). A control that reports how far it is pushed in any direction, not just on or off. It is what lets you walk slowly or run, or steer gently. On the phone it is a draggable circle on the screen.
Analog trigger. A trigger (LT or RT) that reports how far it is pulled, from zero to full. Racing games use it for throttle and brake. On a touchscreen it is simulated by how far your finger slides, as explained in the layout builder guide.
Calibration. Telling the app which phone angle counts as straight ahead, so tilt steering starts from your normal grip instead of the phone's idea of level. See gyro steering.
Dead zone. A small area around the centre where input is ignored, so tiny wobbles do nothing. In GamepadOS it is the setting called Ignore small tilts. See the Settings guide.
D-pad. The four-way cross of directional buttons, used for menus, platformers and fighting games.
Dropped input. A button press or movement that never reaches the game, usually because a Wi-Fi packet was lost at the wrong moment. See dropped or missed inputs on Wi-Fi.
E to L
Firewall. Windows software that decides which programs may talk over the network. If it blocks the PC server, your phone cannot reach it. The connection checklist shows how to check.
Game rumble. Vibration that a game sends to the controller when something happens, such as a crash. GamepadOS passes it back to your phone so it buzzes. It is a switch on the Settings screen.
Gyroscope (motion sensor). The sensor in your phone that measures how it is tilted and turned. GamepadOS uses it for tilt steering, wheel mode and 3D aim. See gyro aiming.
Hotspot. A Wi-Fi network created by a phone, which other devices can join. A PC on the phone's hotspot can talk to that phone directly, which is a handy way to play without a router. See Wi-Fi or USB.
Input lag (latency). The delay between your finger touching the glass and something happening in the game. It is the sum of many small delays, of which the network is only one. See where controller latency comes from.
Jitter. Variation in delay. A connection with a steady 12 milliseconds feels better than one that averages 10 but occasionally hits 40, because you notice the odd slow input more than the average. Jitter is the main difference between a cable and Wi-Fi.
Layout. The arrangement of controls on your phone screen: which buttons, sticks and triggers, where, and how big. You can build your own and share them with a short code.
Lock-to-lock. The total angle a steering wheel turns from one end to the other. In wheel mode you choose 360, 540, 720 or 900 degrees. See wheel mode.
M to T
Pairing. The one-time step of scanning the PC server's QR code so the phone and the PC recognise each other. See how the connection is protected.
Packet. A small message sent over a network. Your controller state travels as a stream of tiny packets.
Packet loss. Packets that never arrive. A little is normal on Wi-Fi and the app is built to tolerate it, but a lot causes missed inputs.
Ping, round trip time (RTT). How long a message takes to reach the other end and for the answer to come back. We quote it because it is easy to measure: about 2.5 milliseconds over USB in our tests.
QR code. The square barcode shown by the PC server. Scanning it with the app tells the phone where your PC is and carries the pairing secret.
Router. The box that creates your home Wi-Fi and connects it to the internet. Where it sits, and which band it uses, affects wireless play.
SmartScreen and Smart App Control. Windows features that warn about, or block, programs they do not recognise. They can stop the PC server installer. See Windows blocked the installer.
Tethering (USB tethering). Sharing the phone's connection with a computer through a cable. With USB tethering, the PC sees the phone as a network adapter, and GamepadOS can talk over it with no Wi-Fi at all. See connecting over USB.
Touch sampling rate. How many times per second the touchscreen checks for touches. Higher means a tap is noticed sooner. See choosing a phone.
U to Z
UDP. A way of sending packets over a network that does not wait for an acknowledgement of each one, so there is no delay waiting for a lost packet to be resent. For fast-changing data like controller input it is a good fit, because the next packet supersedes a lost one. GamepadOS uses it over Wi-Fi.
USB debugging. An Android developer option that lets a computer talk to the phone over a USB cable. GamepadOS can use it as one way to connect over USB, and it should be left on only for computers you trust. See the USB guide.
ViGEmBus. A small driver that lets software create a virtual game controller on Windows. The GamepadOS PC server installs it so that your phone shows up as a normal controller. See why your PC sees an Xbox 360 controller.
Virtual controller. A controller that exists only in software. To Windows and to your games it looks like a pad you plugged in, even though there is no hardware.
Wheel mode. A GamepadOS setting for a phone that you hold or mount like a steering wheel and turn through large angles, for truck and bus simulators.
Wi-Fi band (2.4, 5 and 6 GHz). The radio frequency range your Wi-Fi uses. 2.4 GHz is crowded, 5 GHz is quieter, and 6 GHz is quieter still where supported. See dropped inputs on Wi-Fi.
XInput. Microsoft's standard for Xbox-style controllers on Windows. Most PC games that support controllers use it, which is why GamepadOS presents your phone as an Xbox 360 controller.
Missing a term? Tell us through the contact form and we will add it.
Try it yourself. GamepadOS is free to start: download the PC server and the Android app, scan the QR code and play. Stuck? The support center and contact form reach a real person.