Is the information stored on the device or on your servers somewhere? I like the idea but I'd also like to keep this data for longer than a company may be around for.
+Android and keeping this as device-only-data (aka, no upload/sync) would fetch several $ from me. If I want to be honest on the app and ensure I'm having a meaningful dialogue with past/future me, I do not want 3rd parties to have any means to see that (aka, chilling effect).
I wouldn't mind having them uploaded via Google's backup API. It basically makes syncing settings and what not between devices painless, so if I have to move phones, or I lose mine, I'm not worrying about losing my journal and having to start over. That or a sync to dropbox or some service I can opt into would be great.
Info is saved on the device.