CNET’s Rick Broida published a terrific review of the Spotliter app:
Spotliter app adds real-time effects to your iOS videos
Like an Instagram for video, Spotliter Video offers a variety of very cool filters you can apply while you shoot.
With the arrival of iOS 7, iPhone and iPad users received a smattering of Instagram-style visual-effect filters for snapping photos. But they can’t be used when shooting video.
Enter Spotliter Video, a free app that provides a choice of distinctive filters for video recording. It is, quite simply, like Instagram for video, though without the integrated sharing options.
It works like this: fire up the app, then tap to choose an effect from the scrolling selector along the bottom. Spotliter offers a dozen of them, but not just the usual assortment of sepia, black-and-white, and so on.
Rather, you get effects like B&W2COLOR, which blends the image from black and white on one end to color on the other. But if you tap or drag on the image preview, you’ll see the effect move to match where your finger lands. The same is true of Floodlight, which darkens all but a finger-specific area. If you’re using your iPhone to shoot, say, a fun little home horror movie, you could do some really cool stuff with this effect. More here.