a very simple mobile APP to send notifications to its users

Basically consists in send some special "alerts" to users of this app, an alert could consist on: - Send a pop-up text message on mobile screen (with an url or plain text) - Send a message with an embedded video from you-tube - send a music clip or an image file and every user can view its list of messages received I think a good technical solution could be to use jQuery Mobile and PhoneGap uttilities or frameworks to deploy this app to any mobile device and by using a web site with PHP & mysql database. Please any insight will be evaluated but an easy self-maintenance is our priority.