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Uppy - The next open source file uploader for web browsers
PhotoBulk - PhotoBulk is a bulk image editor for Mac that was created for the best experience of batch editing. With this image editing software for macOS you can add watermarks, optimize and resize pictures, convert images or rename photos in bulk.
Filestack - Simple file uploader and robust APIs for uploading, transforming, and delivering any file into your app. Filestack is a collection of tools and powerful APIs that make it simple to upload, transform, and deliver content.
IrfanView - IrfanView ... one of the most popular viewers worldwide.
Uppy.io - Next open source file uploader for web browsers