Most apps end the take when you switch. This one does not.

When an ordinary camera app changes camera, it tears down the capture session and builds a new one. The encoder stops with it, the file is finalised, and anything recorded afterwards is a second file. That is why switching normally means stopping.

Talk2Camera keeps the encoder running and changes only where the frames come from. The recording never ends, so there is no second file and no join. On hardware that cannot run both cameras at once, a held frame covers the moment the incoming camera takes to open, so the timeline never stalls.

This is the part that makes a teleprompter useful while you are moving. You can read your script, reach the thing you are describing, and show it — without the take ending at exactly the moment the video gets interesting.