[vblord]

Just having the simulator isn't enough for us Xamarin developers. One big issue with Xamarin is that you need a mac (with xcode installed) on the network in order to do builds. If you could solve that issue along with the having the simulator online then you have my money.

[viktorbenei]

Not ideal but you can use an iOS CI/CD / build automation service like Bitrise (http://www.bitrise.io/) (co-founder / CTO here) to do the builds for you. If the simulator service has an API you can even automate the connection with Bitrise.

There are a few online code compilers too like this Swift one (http://swiftstub.com/) to work with.

Certainly not ideal but probably not impossible.

P.S. at this time you're probably better with an OS X VPS.