Photonic is described as 'Flickr client for Mac OS X that let's you upload your photos to Flickr right from you Mac, without having to log into Flickr and upload photos by hand'. There are nine alternatives to Photonic for Linux, Mac, Windows, Android and iPhone. The best alternative is jUploadr, which is free. Other great apps like Photonic are Rightload (Free), Postr (Free, Open Source), F-Stop (Free) and Frogr (Free, Open Source).
jUploadr is a cross platform, cross-site Photo uploader. Currently it runs on Windows Linux and OS X and supports both Flickr and Zooomr. It allows you to set all properties of a photo before you upload it.
Frogr is a small application for the GNOME desktop that allows users to manage their accounts in the Flickr image hosting website. It supports all the basic Flickr features, including uploading pictures, adding descriptions, setting tags and managing sets and groups pools.