It is a Firefox OS application that lets you read any file on OpenDocumentFormat (ODF) format stored in the SD memory your device. OpenDocument is an open standard format for storing office documents such as spreadsheets, text, graphics and presentations file.
Supported Documents are those with extensions, .Odt for text documents, .Ods for spreadsheets and .Odp for presentations
The application of Microsoft Office, has a conversion system and saved to convert any document either word, power point and excel in OpenDocument, soon in future updates will add a system for converting documents directly from WebOffice.
There are some features of Microsoft Office, OpenDocument not supported therefore some things are not displayed correctly, for explanation see compatibilities: Microsoft.com
FoxXapp is a startup (company startup and growth stages). Currently our website is under construction but already offer mobile web applications as you are using. We can not give many details about its features and offer applications for Firefox OS, but if you subscribe, by clicking on our logo, you can receive our updates to keep you abreast of any updates.