Is there a way to save Windows Phone 7 Apps in case I switch to another wp7 phone?

Yeah so far I haven't found out a way to save them, I have an SD 8gb card, but i don't think that would work. + when i think about it, Microsoft is basically ripping you off and taking your money if you were to switch to another windows phone. Non of your apps will be saved and that means you have to purchase them AGAIN! =||||then you should back up all your apps first. the re-install it into new one.