Similarly the P9 has tools for delivering HDR images, night and timelapse photography, special light painting modes, and even direct access to the device's monochrome camera.
I've quickly grown fond of the P9's monochrome photography tools, and its colour effects are ideal companions to Instagram's library of filters.
Perhaps the most important of them is Microsoft's Office Lens, which lets me quickly take pictures of slides and whiteboards, and drop them into a OneNote notebook ready for annotation as part of my personal, searchable archive of meetings and conference sessions going back more than a decade.
It's easy to find big name apps like Photoshop and Snapseed, but there's a long tail of applications that's hard to explore.
Drilling into the app list lets you see reviews, but most of the time they're not particularly informative.
Then there's the perennial issue of identifying the real reviews from real users, and trying to determine how their taste aligns with yours.