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I synched both my iPad and iPhone and then synched them both again (in case anything had got stuck). Then I downloaded the new thing to my phone (haven't done it to my iPad yet), took flipping ages over two hours. Then when I was frantically searching for my lost stuff I saw a big button saying something like 'synch apps' and I just clicked the ones I wanted to put back on my phone. I have also managed to download the photos from my laptop onto my phone (somehow).