Provide an "adaptive icon" for Android launchers

[gnprice]

As upstream docs put it:

… adaptive launcher icons, which can display a variety of shapes across different device models. For example, an adaptive launcher icon can display a circular shape on one OEM device, and display a squircle on another device. Each device OEM provides a mask, which the system then uses to render all adaptive icons with the same shape. Adaptive launcher icons are also used in shortcuts, the Settings app, sharing dialogs, and the overview screen.

This caters to the fact that, for example, the launcher on Samsung devices wants to use a squircle (like iOS), while the launcher on Pixel devices in recent years' versions of Android wants to use a circle.

Currently we just provide a plain non-adaptive icon, which we've shaped as a circle. On Pixel devices it shows up just like that, and it fits nicely with other app icons. On a Samsung device, it's reported to get placed on a white background inside a squircle. The "adaptive icon" feature should let us fix that.

The main work required here is to prepare appropriate image assets. Probably the majority of the work involved in that is in turn to read and absorb the relevant documentation: the UI guidelines page, and the additional resources linked at the bottom of that page.

Because adaptive icons are new in Android 8 O, we'll continue to provide a plain non-adaptive version of the icon for older Android versions. But at this point about 90% of our Android users have Android 8 or later (it was 88% a few months ago), so work we do on this will benefit lots of users.

[adityarajsinghvi]

I can work on it through the android studio we can set all the sizes of the app icons and can do this but how am i supposed to get the app icon of different sizes?

[Signior-X]

@gnprice

The main work required here is to prepare appropriate image assets. Probably the majority of the work involved in that is in turn to read and absorb the relevant documentation: the UI guidelines page, and the additional resources linked at the bottom of that page.

This can be done using Android studio. I want to try this one. Just two questions,

1. From where I can get the logo of zulip. Is there some folder where it is stored.
2. You mentioned that it get's a white background on samsung devices (also on my device), what should be the actual background or behaviour?

[gnprice]

I'll fix this in the new app as a side benefit of the work for #1254.