We haven't had a lawyer go over this yet, so it's not perfectly rigorous. Instead we'd like to start out with a simple honest statement of intentions. We'll probably mess up sometimes, but try to make things right.
1. Your data is yours. If you want a copy of it, you can have it. If you want us to delete everything we know about you, we will.
2. We'd like to borrow your data to make things better. The whole point of this service is to collect information in a way that's good for you. Sometimes that's analyzing your specific personal data to help you find patterns. Sometimes that's analyzing patterns across all our users, for example: knowing which features all our users get the most out of so we can focus on making those better.
3. Privacy matters. We will go out of our way to not spy on you. When possible we'll only look at summary statistics rather than individual users. But, sometimes a bug only shows up when a user records eating nachos at 00:01 am. We don't judge. Your secret is safe with us. Also, we will do what we can to keep out hackers who might want to use this system to spy on you.
4. Selling/sharing data. Right now we're against it. We would rather build a business where the value comes from satisfying our customers and you see that value and paying us a few dollars a year is worth it to you. At some point in the future we might try an ad-supported model, but if we do it will be optional and opt-in and we won't share or sell your data without asking you first. See point 1, your data is yours.