Use this topic to share some knowledge among your fellow Koders about various tools available there which you use or think might be helpful in app development. So, let me start it first.
Moqups
So, basically Moqups is an online tool which allows users to create wireframes, mockups or UI concepts, prototypes depending on how you like to call them. I personally use it to make a mockup of my app before actually starting its development. It is very easy to use and you can drag-and-drop components to design the mockup of your app.
Allows make Material app icon for your app. You can use most of icons from Material Icons but you can also upload your icon/image and you can add text instead of icon.
Also, you can make other assets with Android Asset Studio. Like Title Bar Icon generator, App Shortcut Icon generator and more…
(like me 
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