Um is it free or not??!!!

Ok first of all this app is AWSOME!!! But when I got it, it was for free , I swear it said free...but when I told my friend to get it, she said that it was 0.99 cents, when I went to check, she was right! But I know when I got it, it was free. So did I mistakenly buy it??!!!! Cuz I swear it was free. Anyone else got it for free?

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