The trend toward flat design hit big in 2013 with newer user interfaces of Windows 8 (“Metro“) and iOS7, and website and logo redesigns by Google and others. As part of a general move away from skeuomorphism, Adobe application design elements “flattened out” after CS5. Flat and thin may be in, partly due to hi-res screens, but a missing dimension of “long shadows” added to flat elements became popular too.
Long shadows are stylized 2D elements that are “at least 2.5 times the diagonal of the object…at approximately a 45 degree angle, preferably towards the right,” according to early promoter Jeff Escalante. The long shadow meme was surveyed with design examples, Photoshop Actions, and CSS utilities in Flat Long Shadows: Step-by-step Tutorial, Resources and Examples by Awwwards, the The beginner's guide to flat design by Luke Clum, and in Long Shadow Design – A New Trend? by Thoriq Firdaus.
Flat design and long shadows were noted as a trend by Videomaker in 5 Motion Graphic Design Trends For Every Video Editor In 2014, and tutorials on the unreal long shadows started appearing last year — along with the flat elements of AE Sweet and similar circle effects. These stylized shadows are created in similar ways as one might expect in Photoshop with layers and mattes, but not using 3D lights, Lightburst and Drop Shadow, or more complicated ways as one might expect in After Effects. The tutorials are all good exercises in quick thinking on After Effects basics.
Mikey Borup showed how to animate “long shadows” in his After Effects Tutorial intro logo tutorial.
Daniel Brodesky posted Create Long Solid Shadows on Your Logo:
Mikey Borup improved on his earlier tutorial, using blur and matte on layers in Long shadows in After Effects tutorial. He also has a demo using his $1 preset, Long shadows real time build – Fast and Easy. Later he added Long Shadows Preset v2.0 (below):
Evan Abrams followed up with Long Shadows (with the repeater), a quick and easy way to make long shadows using the repeater and some shape layers (ironically, it's longer than the last Borup tutorial). There's also a free project file.
If that's not enough, there are also templates available, like The Ultimate Long Shadow Toolkit:
Further info on flat design might be found in the Lynda.com course, Mograph Techniques: Creating a Flat Vector look using C4D and After Effects with Eran Stern.
Please note that this roundup is for quick review and comparison. There is almost always vital information from the originating authors at the links provided — and often free presets, plug-ins, or stock footage too.