This app was mentioned in 5 comments, with an average of 1.40 upvotes
I use this app: https://play.google.com/store/apps/details?id=com.easymobs.pregnancy
And take it easy. Don't go too hard on yourself and just slowly prepare for bub. Save up money or afterpay stuff if needs be. That's the best advice I can give you.
I have installed an app called Pregnancy Tracker (link here: link) and I don't remember it asking for an email address at all. It just asks you for your due date or last period. I even just checked in my settings for it, and I can't find anything about email.
Also: may I please recommend this website: https://www.familyeducation.com/pregnancy/week-6-pregnancy/you-are-6-weeks-exactly-pregnant
(You can click through to the exact day you are in your pregnancy.)
I've bookmarked that site on my phone and check it each day! It's so informative.
I use Pregnancy Week by Week. It lets me track what I want to track, and isn't too heavy handed with all the things mom is "supposed" to be doing (I let my doctors and the book Expecting Better be my guidance there).
https://play.google.com/store/apps/details?id=com.easymobs.pregnancy
I like this one. Has daily blurbs of information that has been useful.