Why am I unable to react to videos on an iPhone 5c?

Unfortunately, Apple only support screen recording after the iPhone 5s. Therefore, users with devices older than the iPhone 5 would not be able to record a reaction :(

For a list of devices with screen recording, checkout the Apple website.

If you are using a device newer than an iPhone 5s but unable to react to videos, do get in touch with REACTION.CAM Support by submitting a request on the App or send them to [e-mail].