Do WinJS or Windows 8 javascript apps in general support writing blobs to file? All the examples and documentation I have found only mention writing text. I need to store binary data within the application, not user defined via a file picker.
In case it does not, what's an alternative? Writing base64 strings? Or better look into IndexedDB?
You can use a variety of techniques, but if you'd just like to write an array of bytes for example to the file system, you might use PathIO.WriteBytesAsync. Have a look at the other methods of PathIO for simple ways to access the file system.
IndexedDB may not be the best fit depending on the amount of data you need to store. There's a limit of 250MB per application for example.