The following step-by-step tutorial is going to show you how to convert MKV to iPhone 4S video using MKV to iPhone 4S Converter so that you can transfer MKV files to iPhone 4S and play MKV video on iPhone 4S.
Download and Install MKV to iPhone 4S Converter
Download the latest version of MKV to iPhone 4S Converter. Install and launch it.
Add MKV Files
Click the "Add Video" button to import the MKV file. Alternatively, you can click "File -> Add Video Files..." to add the MKV file. You can also batch import MKV files by clicking "File -> Batch Add Video Files".
Choose Output Format
From the "Profile" drop-down list, choose iPhone MPEG-4 Video as the output format.
Note: You can also adjust the audio/video parameters to customize a specific profile that best fits your needs. Click to learn how to customize profile.
Start Converting MKV to iPhone 4S
Click the "Start Encode" button to start to convert MKV to iPhone 4S.
Transfer Output to iPhone 4S
After you get the output files, launch your iTunes and transfer them to your library. Then you will be able to transfer the converted files to your iPhone 4S with the sync of iTunes.