Does anybody know how I can export apps?
Also, what's 'signing apps'?  How does it work?

Signing apps means packaging an application in TI's *.8xk format, with a digital signature (the 0104 key) so it can be sent to a calc. If an app is not signed, the calculator won't accept it (and I think TI-Connect won't even try to send it?). An app would run fine unsigned on a calculator (if compiled there using Axe), but if it wasn't signed it couldn't be sent to a computer.

For instance, ZDS (Zilog Developer Studio, one way to make apps- the only example I can think of) produces *.hex files. This contains all the code needed for an application. But you cannot send it to a real calculator without signing it first.

The 0104 key is the only signing key TI actually released, and it can be found in their 83+/84+/73 SDK along with Wappsign, a program to do that.

But Rabbitsign, a community-made program, can also sign apps, along with z80 OSes, 68k apps, and 68k OSes- as long as you download all the keys from BrandonW.net.

Does that explain it?

That's Wappsign- by "SDK" I meant "Flash Debugger". I knew there was something else it was usually called.

It does what it's supposed to do. I doubt it works with anything but a z80 app- don't know if it would work if I tried to run the TI-73 app signing key through it (I don't have a TI-73 app source to try, anyway). It also has a GUI.

Nope, it's a commandline program.

But it also serves as a linker for assembly programs, which Rabbitsign can't do.

I'm fairly sure Wabbit does allow unsigned apps because I'm pretty sure I've tried some and then later people are apologizing for not putting a signed one up.

Wabbit does indeed accept unsigned apps...were too lazy to write a validator (although i suppose i could steal code from spasm). If you would like to check to see if an app is properly signed without sending it to a calc (the calc actually writes it to flash then erases it if it fails to validate), you can reset all memory on wabbit then load the app. This will simulate sending the app the long way and the os will actually validate it

Yeah, I've noticed the delete thing, which really bugs me.  Perhaps we can patch this out?

I don't know much about patches, but I can look into it.

No, they will run, but only up to 16 times.  Also, Wappsign can do it as well as rabbitsign, even though I prefer rabbitsign for its versatility.