What is mkv?The Matroska video format has become popular in the anime fan-subbing community (where users create subtitles) since it supports multiple audio and subtitle tracks in the same container. The Matroska Multimedia Container is an open standard free container format, a file format that can hold an unlimited number of video, audio, picture or subtitle tracks inside a single file. Matroska file types are .MKV for video (with subtitles and audio), .MKA for audio-only files and .MKS for subtitles only. The most common use of .MKV files is to store HD video files. MKV files can also be played on Palm, Symbian, and Pocket PC mobile devices using the CorePlayer Mobile software.
What is 3gp?3GP (3GPP file format) is a multimedia container format defined by the Third Generation Partnership Project (3GPP) for 3G UMTS multimedia services. It is used on 3G mobile phones but can also be played on some 2G and 4G phones. Audio and video container format developed by the 3rd Generation Partnership Project (3GPP); designed as a multimedia format for transmitting audio and video files between 3G cell phones and over the Internet; commonly used by mobile phones that support video capture.
The simple to use and intuitive operation of
MKV to 3gp for Mac brings every 3G mobile phone user a completely new experience. You can not only convert MKV and a variety of other popular videos, movies and songs to 3gp for playback on 3gp playable phone, but also let you play with video editing to get the desired output video. MKV to 3gp converter for Mac ALWAYS delivers the best video with the least time.
Now, let's get to the detailed, step-by-step tutorial on how to use
3gp converter for Mac to make videos and audio for mobile phone:
Step 1 We assume you already have 3gp converter for Mac (V3.3.8) installed on your Mac. If not, please download it from www.iorgsoft.com and install it.
Please don't worry whether the program would be compatible with your computer or not, with the capacity to run on both Intel processor and PowerPC it will eliminate the incapability issue.
Step 2 Hit Add File to load video info.
This would open a window, browse for the video files you wish to convert. Select the files and click the Open button. The program supports batch mode, so please feel free to load as many as you wish.

Note: video and audio files are both supported.
Step 3 Convert video
Please appoint 3gp or others as output format for the video needed to convert, you can do this in the pull down list of Profile. You also need to select the output path in the Output drop down list. After the conversion, click open will show you where the converted file located.

Optional step
Step 4 There are many optional choices can make your video look more personalized, such as add Effect, Crop out unwanted part in the frame, trim video, capture screenshot in the frame.
Want to crop out the black sides in the frame? Well after you load the video, click Crop...this opens a window for you to tweak the numbers to decide how much area you want to leave out. You can put in specific numbers like it shows below:

Related tutorials: How to convert avi, flv, asf, wmv, 3gp, 3g2, mov, vob, mpg, mp4, mkv, m4v, dv to 3g2, 3gp, mov, mpg, mp4 on Mac OS X?