Android multiple screens explains how to build an application that fits different screen sizes and densities. Though the system performs scaling and resizing to make your application work on different screens, you should optimize your application for different screen sizes and densities. Doing so will enhance the user experience and your users will strongly believe that your application was actually designed for their devices. Before learning how to support multiple screen sizes and densities, it is important to understand some terms such as: How to Support Multiple Screens:

1. By declaring the screen sizes your application supports, you can ensure that only those devices with the screens you support can download your application. Declaring support for different screen sizes can affect how the system draws your application on larger screens—whether your application runs in screen compatibility mode.
2. To declare the screen sizes that your application supports, you should include the <supports-screens> element in your manifest file. [code lang="xml"] [/code]
   
3. Provide different layouts for different screen sizes. The way we place an object onto the screen is an aspect that requires consideration. It has to do with the resolution because we can have more or less space to place our components. Android provides a smart way to handle different layouts for different screen sizes. If we want to support all these screen sizes, we have to map these android names into the directory structure inside the res directory. The convention used by android is to add these names at the end of the layout word.
4. As you can see in the image, each directory contains the same elements with the same names. The only thing that changes is the content of each element, which suggests that you need to just adjust the textSize or marginTop element. Try to set the width and height attributes value using wrap_content and match_parent, and, try to avoid the usage of dp.
   
   
   
5. Provide different bitmap drawables for different screen densities. Android scales your bitmap drawables (.png, .jpg, and .gif files) and Nine-Patch drawables (.9.png files), so that they render at appropriate size on each device. You have to set different image resolutions for different screen densities.

Density changes the way image looks on various devices. An image looks right on one screen and looks too small in a different device with a higher density. This issue needs consideration. Android groups devices into categories based on their screen density. A set of generalized densities: To create alternative bitmap drawables for different densities, you should follow the 3:4:6:8:12:16 scaling ratio between the six generalized densities. For example, if you have a bitmap drawable that is 48x48 pixels for medium-density screens, all the different sizes should be: Android also has tvdpi support which is 1.33*mdpi. Like we did for layouts, we can build a directory structure under the directory res that maps these names. This time, instead of a layout, we use a drawable. So we will have: