I began a quest for personal finance / accounting software that will help me keep tabs on my cash flow / net worth.  Mint did a decent job for me previously, and Credit Karma is less adequate.  I read a forum post on ...

Installed dedicated app.

Another example - I had money with Donut -an app where you can invest cash and earn interest in DeFi...well, I was earning anywhere from 5-8% (sounds great, right), until one of their partners got caught up in the FTX collapse and now those funds are frozen and I may or may not get them back.

And what is a "mileage book" anyway in the age of navigation apps?

They have an app, scan your mail, forward mail, and will even deposit checks (forward/mail to your bank).

The app doesn't allow rent by room, so I am sort of forcing it.

https://www.arcgis.com/apps/webappviewer/index.html?

I just started researching Baselane, along with Stessa and Azibo These apps look very promising and interesting.

You can download the Meetup App and search for BP Lake Charles Meet Up.

Your app concept sounds promising!