1) its was a FREE app, *don't we just all love freebies!?*
2) a friend suggested it, and you wanted to be a "good friend" so didn't say no
3) it has some practical use... *whatever "practical" means to you*
4) you have no life, other than your phone, and it must be provide everything that it necessary for human survival, which does not exclude pleasures such as drinks, sex, and vibrating stimulus
5) you have seen an advertisement and heard "there's an app for that" and then downloaded it just to see what it was actually like
deletnamehere: I don't know, stop scrolling through all my pages of apps!
insertnamehere: You are ridiculous!! I can't believe you're an app hoarder!! :P