I like the service, although I would recommend them a more positive connotated name for future growth... I get the association with Exorcism, when I read their name...
The FAQ explains it as nothing to do with exorcism despite being "one vowel away", and instead references "exercises". But then goes on to make a reference to the "devil" being in the details of constructing the exercises.
Honestly it baffles me and turns me off the project. I wouldn't want to think about that concept every time I was engaged in learning. It may also be an issue for various cultures for whom exorcism is a common sacred tradition.
For example in parts of Africa - exactly the type of market a good-will project such as this would ostensibly be targeting.
Another comment says they're struggling for funds. Whether directly related or not, a name with a hugely dark connotation, that springs to mind so immediately they mention it second in the FAQ can't be helping.
