App: FrameStacker
Developer: Trevor Alyn
Genres: Photo & Video

FrameStacker is great for creating star trails, streaky clouds, and interesting sports videos.

FrameStacker lets you stack the frames of a video using a wide variety of blend modes. You just choose a movie file, pick a blend mode, and specify how many frames to combine when building each frame of the output movie. For some videos made with the app, visit https://www.youtube.com/playlist?list=PLNoXydjy2lnOMNCnf5PEkaej6eCP9WOS2 .

FrameStacker can stack frames with all of the following blend modes. (Note that not all of these blend modes produce interesting results; in general, you'll want to stick with Lighten or Darken. But I included all of them just for the sake of completeness.)

Lighten
Screen
Darken
Multiply
Overlay
Color Dodge
Color Burn
Soft Light
Hard Light
Difference
Exclusion
Hue
Saturation
Color
Luminosity
Clear
Copy
Source In
Source Out
Source Atop
Destination Over
Destination In
Destination Out
Destination Atop
XOR
Plus Darker
Plus Lighter

Release notes: