Best photo editor for Android
Snapseed's got a clean, easy to use, interface, plus it supports raw, includes all the important retouching tools and delivers good results. And it's free.
Best photo app for Android
For mashups, filters, shape overlays, collages, frames -- pretty much everything you can do with a photo -- PicsArt delivers in an easy-to-use and attractive app. Plus, it supports raw photos and you don't need the in-app buys.
Best selfie app for Android
Cymera isn't just a selfie app, but it has options like spot metering and a stable shooting mode which make it possible to get the best results. Plus it has all the filters and retouching tools you'd want and its ads don't get in the way.
Best camera app for Android
A free, open-source and full-featured manual camera that delivers very good photo quality and 4K video. It's not the prettiest, but it's easy to use. And it finally rolled out raw support.