Please try cartoview www.cartologic.com/cartoview cartoview is an open source application framework to deploy web maps you can use cartoview independently from server products or together with open source software like geoserver or with ESRI ArcGIS server.
Cartoview is extensible via apps in the same way iphone or android operates, take a look at the cartoserver app which works with the same web standards as arcgis server and you will be able to make good use of all ESRI web mapping templates in a fully open source environment.
Take a look at the samples at http://www.cartologic.com/cartoview/demo/