MP4s work better than AVIs on most of the portable devices. Most video players can interpret AVI files, but you may find need to convert AVI to MPEG-4 if you’re an Apple product user – be it iPod, iPhone or iPad. You need files in the MPEG-4 format to play them on your iPods, iPhones or iPads.
AVI or Audio Video Interleave format, is a video file format created by Microsoft in 1992 to play videos on Windows. AVI files employ minimal compression, which usually results in large file sizes with high-resolution videos. AVI files can contain both audio and video data in a file container that allows synchronous audio-with-video playback.
MPEG (pronounced M-peg), which stands for Moving Picture Experts Group, is the name of a family of standards used for coding audio-visual information (e.g., movies, video, music) in a digital compressed format and was introduced in 1998 and is still considered a developing format.
The major advantage of MPEG compared to other video and audio coding formats is that MPEG files are much smaller for the same quality. This is because MPEG uses very sophisticated compression techniques.
There are quite a few conversion programs, but we will use a slew of free online tools to convert AVI into MP4.
Go to Zamzar.com
Click “Choose File” and find the AVI you wish to convert. Next, select “MP4″ for your target container. Free users of Zamzar only upload and convert files up to 100MB in size.
Type in your email address and click “Convert.” You’ll be sent you an email containing your MP4 inside of a download link.
Go to Mediaconverter.org
Click the “Upload a file” button and find the AVI. Afterwards, select “MP4″ for your output container. Mediaconverter restricts upload size to 100MB for free users.
Click “Start” to create the new file. After the conversion winds down, click the download link to grab your MP4.