For iPhone users, it all begins with iMovie, Apple's free editing app optimally designed for use with the iPhone's touchscreen. Beyond basic editing, it also helps you add effects, and even create a soundtrack of your own. If you have an Android phone, you'll want to use FilmoraGo, which offers an array of classic transitions, overlays, and filters.
Little Camera, Big Dreams
FilmicPro is the app that turns your little phone into an HD video camera capable of creating footage worthy of the big screen. It gives you full control of shutter speed, exposure, and focus, allowing you to merge the ease of digital technology with the range of control traditionally offered by analog.
Action Sequences on Demand
With the help of FXGuru, both Android and iOS users can turn any mundane clip into the stuff of action movie lore. Whether you're in search of robot-induced mayhem, an aerial attack, or the arrival of alien life, FXGuru can help you realize your wildest blockbuster movie dreams.
If you've been dreaming up time-lapse sequences to run between the scenes of your film, you'll want to get Hyperlapse for Instagram. Putting Instagram's built-in stabilization to work, this app helps your phone create the type of footage that used to require lugging around a tripod all day. You can even speed up your videos to 12 times their original speed, meaning that sunrise shot you've been planning will definitely be able to make it into the final edit of your short film.
When it's time to overlay the title—or the end credits—VidLab makes it easy. It helps you create and animate text, as well as effects and filters, and makes it easy to weave in any old footage or imagery you have saved on your phone. (Better start working on that production company logo.)
BONUS: A Little Help for Your Lens
This is the device used to great success by Sean Baker in his direction of Tangerine, the award-winning film shot almost entirely on an iPhone 5S. This adapter, made of anodized aluminum and glass, allows you to shoot wide-format, panoramic images with just your phone camera.