[skinnyfoetusboy]

The first post from Wired[1] about Instagram refers to it as a free app. I could see OP "misremembering" buying Instagram.

[1] https://www.wired.com/2010/10/instagram-for-iphone-like-a-lo...

[jerrre]

Maybe confused with Whatsapp? A used to be paid (is it now?) app bought by Facebook?