The biggest gain is the security of all of the code running on someone else's hardware.
The biggest loss is also security: all of your keystrokes, passwords, traffic, etc. are stored on someone else's hardware.
> The biggest gain here is security, you won't ever run code natively. The caveat is you also have to trust the host.
That assumes any malware cannot bust out out of mightyapp's sandbox to the host's host.
The biggest gain here is security, you won't ever run code natively. The caveat is you also have to trust the host.