You can automatically view multimedia messages on Android phones by changing the settings in your messaging application. To do this, open your chosen messaging app, and click on the settings for the application. Find the "retrieve message settings," and select to auto-retrieve messages. After doing this, you will automatically view multimedia messages when they are sent to you.
Most devices do not automatically accept multimedia messages due to the possibility of exploits or malicious scripts or coding being run automatically. One example of such an exploit is the Stagefright bug.
The reason for disabling MMS by default is that oftentimes, users receive a message from a friend that they are required to download in order to view the file. In many cases, this download attempt fails, and so the message is never able to be seen. In frustration, many users hastily change settings without realizing that they are opening themselves up to any threat at all.
MMS traffic reached over 200 billion messages by the end of 2013, according to Portio Research. These messages are mainly sent through the United States and China. The wide use of MMS among so many different people makes the use of automatic MMS downloading an increasingly common practice.