There are three aspects that occur to me right now:
Any personal information I collect from you – including, but not limited to names, email addresses, questionnaire answers, and personal emails – will only be used by Wossname Industries for the express purpose of providing you with whatever service we're offering you. In particular, I will not pass on any personally identifiable information (e.g. your name and/or email address) to any third parties without your express permission.
I may aggregate information collected across a cohort of users, and share that aggregate data with others. I'll only do so if I've got a good business reason for it. (For example, if I'm talking to a podcast network about partnering up, I may share the number of subscribers in order to demonstrate that there's an audience for it! Or perhaps I'm talking to an investor about helping me to fund growth in The Happiness Project, and I want to show the improvement in happiness that existing users have achieved.)
I do use a number of third party services to run the business, and your data is stored with some of them. In particular, right now, I'm using Intercom for handling email, Mailchimp for mailing lists, and Typeform for questionnaires. I'm pretty confident that they're not going to do anything evil with your data and I'm pretty careful about having strong passwords, and two-factor authentication enabled, so my accounts should be secure enough.
That's pretty much all I've got to say on privacy right now! If you've got any questions at all, please feel free to get in touch. You can send me a message by clicking the wee chat bubble in the bottom right hand corner (that's Intercom at work!), or by sending me an email, to email@example.com.