Seems like a great thing to pitch to universities and schools.
Can't see the use for general development. Hosting costs for your own slice is so low, and it gives you so much more freedom that a developer would have to be crazy to limit their options to only what appjet give them.
Plus AppJet is still a small company so its not going to have the scalability of something like EC2 or Google AppEngine.
I actually agree with your assessment that AppJet seems limited as compared to renting your own server or part of a server, for general development. The original idea of AppJet was for it to be a place for simple 1-page apps -- apps where the effort required to set up hosting greatly exceeded the effort to code the app.
A natural extension of this was to write a guide to teach people how to program. AppJet is still the only place I know of where you can learn to program and actually build an app that you can share with friends via a URL, all without downloading any software or configuring a development environment.
Now we are working on addressing all the limitations of AppJet as compared to having your own server, and therefore make it a platform that you'd use for more "serious" apps, not just 1-pagers. Hopefully when we release the next version, you'll give us another look and decide we compare favorably to the alternatives for general development.
It took me all of an hour to go through the entire online reference. It is clear and easy to understand. But its pretty barebones at the moment. What it lacks in extended features though, it seems to make up for in simplicity. so if a developer community can produce well written wrappers for existing Java libs there may be a future for it.
The docs do not show any details on how their object storage engine works. The API is pretty simple. It isn't hard to provide a very robust storage engine that provides such an API. Their FAQ (I think) however does state that they have been running for about a year and have never lost any data; if that means anything ;).
I would think that if appjet were to gain significant traction, you would need integration into other persistent options such as MySQL and Postgres. The easiest thing (I'm guessing) would be to just write simple js wrappers to an existing Java based ORM.
Wow, I sure am answering a lot of questions about appjet considering I just discovered it a few hours ago!!!
