You don't have a server to run the server side of pombo ? http://sebsauvage.net/pombo/index.html or http://bobotig.fr/contenu/projets/pombo/

You can have one free at Google App Engine ! at http://code.google.com/appengine You got 1Gb of datastore free quota to store your pombo files

Just customize app.yaml and you're ready to go