The application can be used offline, without the need to be connected to Internet, but the problem now is that MobiOne Studio doesn't appear to be available anymore. The developers don't offer the possibility to download and install it on PCs. Instead, they have other applications you can use to develop apps for mobile platforms and I recommend checking their website for additional information.
These are the new products offered by the developers: https://www.genuitec.com/products/
