Open source budget tool My Expenses on Android (F-Droid)

Hello,
I’m beginning with budget after postponing it for more than 2 years. My privacy friendly setup (I want to avoid closed source solution and cloud based ones to manage such sensitive data, I have a NAS and can sync to WebDAV or FTP, or Nextcloud running on my NAS).
I have started with a LibreCalc spreadsheet, define categories and start filling a budget for each.

Now I have a pile of receipts accumulating since I decide to officially start 1 Jan. Some are one category but some are multiple. I decided to use My Expenses on Android (open source software with many options, advances ones are paid, I don’t use them so far) to enter these expenses and then export them in CSV to my spreadsheet and (when I will solve my small formula issue with the non-formatted dates) I should have the automatic sorting of expenses by categories and by month from a single tab raw source from My Expenses.

Now my question is: does anyone have experiences with My Expenses on Android? If yes do you use it as complement for a Spreadsheet like I plan or do you use it only for you budget and tracking (with the paid version, but it’s much cheaper than YNAB anyway)?

Advantage of the spreadsheet is that I can adapt it the way I want with more or less time spend initially (I’m already quite advanced with it). But still I need a way to check some categories on a mobile from time to time and sync with other devices in the family (always more difficult than doing alone). I guess I could use My Expenses (or another tool on mobile) to do most of what I’ll do with the spreadsheet but then I have the initial effort to change my way of doing according to the software possibilities and limitations.

So any advice with this software, with other open source Android software or with a mix usage of spreadsheet and a mobile software is welcome.

Have you considered Beancount? There’s seemingly also a free app available: https://play.google.com/store/apps/details?id=link.beancount.mobile&hl=de_CH&gl=US syncing with Nextcloud should be possible…

The initial setup is a bit complex but then rather easy to use.

Thanks for the tip. I’ve quickly look at it and it looks quite raw, with the settings in a text file. If my wife has to use it at some point, I need a minimum usable UI.