Making feature films with cheap video equipment, supplemented with lots of computer processing, is nothing new. Many scenes of blockbuster films have been made this way, even if the entire film is not. And a few hit movies in recent years have been filmed this way entirely. The difference between actual location, a set, or computer graphics is almost nil in the eye of the audience, so this liberates the film makers from the costs and hassles of staging scenes in costly locations. With computers as cameras you can generate whatever you can imagine.
That part of film magic is evident in any "making-of" movie. What's new is that the new camera/apps are steadily coming becoming like a word processor -- both pros and amateurs use the same one. The great script is not due to a better word processor; it's how the great write uses it. Likewise, a great film is not due to better gear. The same gear needed to make a good film is today generally available to amateurs -- which was not so even a decade ago. Film making gear is approaching a convergence between professional and amateur, so that what counts in artistry and inventiveness.
The newest frontier shaped by this parity seems to be making large-scale films without a lot of extras. Computer generated crowds were first used a decade ago, and reached some public awareness in the Lord of the Rings trilogy. In this memorable scenes batches of smaller crowds were replicated computationally to produce very convincing non-repeating huge crowds. But if you are cheap, desperate and inventive, smaller crowds can be generated from no crowds at all -- just a couple of people.
Here's a clip demonstrating how a World War II D-Day invasion was staged in a few days with four guys and video camera.