You can make an iOS version of your Android app on Win7 using basic
HTML, then use
build.phonegap.com to make the .ipa file. You can then
use iTunes on your Windows PC to test the .ipa on any iOS device you
have. However, you'll need a Mac to actually upload the file to Apple
for approval. Annoying, but Apple's out to sell hardware, not
services. As has been said, you can either buy a Mac Mini (as they are
the cheapest), or you can google for ways to install OSX as a virtual
machine on your current computer.