Is It Snappy is a free utility app available on the iPhone platform. Developed by Chad Austin, this app allows users to measure the input-to-output latency of various devices such as text editors, game consoles, televisions, and more.

Using the high-frame-rate camera of your iPhone, Is It Snappy lets you record a video of the button press and the resulting effect on the screen. The app provides a frame-accurate scrubbing UI, allowing you to mark the precise input and output times. It then calculates and displays the difference in milliseconds.

With Is It Snappy, you can objectively quantify the responsiveness of your device, text editor, display, or video game. Whether you're a developer, a gamer, or simply curious about the performance of your devices, Is It Snappy provides a valuable tool for measuring and analyzing input-to-output latency.