As ArsTechnica points out, testing whether a carrier is throttling is complicated. Online services themselves can play a big role in service quality. For example, YouTube and Netflix automatically change video quality based on network speed.
Other factors that can affect speeds include how each service is structured, what content delivery networks (CDN) are used, and how far away a user is to that CDN. The app doesn’t seem to present this nuance; rather it gives you a binary answer of “Differentiation: Yes; Differentiation: No.”
As an example, Verizon started throttling network speeds when the FCC was still chaired by Tom Wheeler, who led the net neutrality rules. The carrier said at that time throttling was allowed under an exception to the rules concerning reasonable network management. The FCC didn’t challenge Verizon on this.
Current net neutrality rules clearly state that providers may employ reasonable network management practices to ensure that their networks and services run efficiently and work well for their customers.
Video optimization is a non-discriminatory network management practice designed to ensure a high quality customer experience for all customers accessing the shared resources of our wireless network.
On Twitter David says that Apple has actually recently approved the app today. It doesn’t appear to be the on the App Store yet, so stay tuned.