I use Snapseed on Android. It's a practical app with many photo editing tools
I like how I can edit my photos here,
HandBrake - HandBrake allows users to easily convert video files into a wide variety of different formats.
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dmMediaConverter - FFmpeg GUI
PicsArt - Explore 100,000,000+ awesome images and photos on the web
Format Factory - Format Factory is software that allows the user to convert media into various file formats. The software is a product of PC Free Time, a Chinese software development company. Read more about Format Factory.
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