Free download 3GP Converter via the link below, install and launch it, then follow this gudie on how to use 3GP Converter.
Step 1. Add Files
Click 
to load video or audio files from computer or other devices(like USB device, camcorder, MP4 player, etc) directly.
Step 2. Select output formats and destination folder
Select proper output formats from the drop-down list of "Profile". Then select destination folder for converted media files from the drop down list of "Output".
Note: You also can click "Advanced..." to customize the output settings in details . You can set the video resolution, frame rate, audio channels, bitrates etc.
Step 3. Edit videos (Optional)
Click 
to trim video and set the start time & end time to get multiple clips as you like. Or click 
and you can crop the frame size, append effects, add picture/text watermark, or edit subtitle.
Step 4. Start Conversion
Once you've finished all the settings, click on "Start" button. After conversion, you can click the Find Target button to open the output folder and find the converted files.
That's all. Just free download the 3GP Converter to have a try by yourself now!
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