Figma

Figma is the only app I've found to work with Sketch files on Windows. There are others, but they all fall short one way or the other. As a developer exporting assets yourself, you need control over layers, groups, and export settings. Figma nails all of them. I can't speak to it's merits as a design tool but I can tell you exporting raster or vector assets for Android apps works easily and exactly as expected.

Affinity Designer / Photo

On occasion I get already exported assets but sometimes they are the wrong size, have extra padding, or weren't exported optimally. In this case I reach for Affinity rather than deal with back and forth. Ever try to import an SVG and have Android Studio throw a bunch of warnings? Or maybe it looks great in Chrome, but messed up once converted to a Drawable XML resource? Open in Affinity Designer, then go to File > Export > SVG > Preset > SVG (for web). Tap Export and your SVG should be ready to go. It's cheaper than Adobe CS and covers both work and play quite well.

Instant Eye Dropper

Instant Eye Dropper does exactly what it says on the box - give you a quick way to capture a hex color code from pixels on your screen. Click and drag the system tray icon, then release over the pixel you want. The hex color is now in your clip board! This is useful for dealing with screenshots or other flat files you may come across.

BandiCam

If you ever find yourself needing to asynchronously share your screen, this is the app to do it. There are free options and very expensive ones, but BandiCam strikes the balance between features, ease of use, and price. It's also one of the few that can handle recording a 4k display at high frame rates and without steep compression or tearing.

Lightshot

Windows built in handling of "prt sc" is kind of lame. Lightshot gives you a quick and easy way to capture your entire screen or just a portion. You can annotate it right there, save it, or just copy to clip board.

So that's it, my top Windows tools for dealing with the more visual tasks I face while developing an Android app. Let me know what your favorites are.