I'm impressed at the features and simplicity, but I'm wondering what the real use cases are. If filters were a core part of my business, I'd certainly be doing

I'm impressed at the features and simplicity, but I'm wondering what the real use cases are. If filters were a core part of my business, I'd certainly be doing them in-house instead of relying on a 3rd party service... Especially when it comes to the basic operations (crop, resize, etc) which can simply be done with imagemagick (or rmagick). Even Heroku allows for those operations on temporary files, despite the read-only filesystem. That said, the "real-time" feature seems like it could make certain use cases much easier. (An alternative to firing up workers and returning an intermediary status to the client.) Also, I suppose apps without much server infrastructure (built on more limited PaaS offerings) could benefit from this API.