While Windows Phone has always had great native support for uploading images to social networks, you have to do it one at a time. SNUpload helps to solve that by allowing you to upload your images to multiple networks at once.
SNUpload is a handy little app for both Windows Phone 7.5 and 8 users that will let you caption and upload an image to both Facebook and Twitter. The advantage this app has over native Facebook and Twitter integration, besides simultaneous uploading, is that you can have multiple Facebook or Twitter accounts plugged into the app. While the majority of you may only have on account per social network, this app can be handy for people running multiple Twitter handles.
Future updates to SNUpload will bring support for Flickr, Pinspiration, Dropbox, SkyDrive, Facebook pages and Box.com (though SkyDrive might be a bit redundant).
The app is worth checking out if you share the same pictures across your social networks and promises to get better over time. Unfortunately, there is no trial version, but you can pick it up for $1.29 right here in the Marketplace or use the QR code below.