As for doing this kind of thing with Twilio, here are the two building blocks you'd need:
Twilio + Python: https://www.twilio.com/docs/sms/quickstart/python
Python + Google Spreadsheets: https://www.twilio.com/blog/2017/02/an-easy-way-to-read-and-...
I like it
We also couldn't figure out the YNAB methodology. I know people swear by it, and we probably just didn't put in enough effort. But we attended a webinar, made it one month, then couldn't figure out how to duplicate our budget for month two. It was just different than how we are used to thinking about finances.
Also -- and this is probably the biggest thing -- I built it myself. For 99.999% of the population, YNAB is an objectively better product. But as a developer, I can't overstate the satisfaction that comes from my wife using something that I built multiple times a day.
- budget tab: tracks category + allocated budget for the month
- expenses tab: tracks date, amount, category, description
- when we spend money, my wife and I text, eg, "13.31 restaurants lunch at chipotle" to a Twilio number. A flask app splits the body of the SMS expecting "X.XX category description", and uses the Google spreadsheets API to add the row to the expenses tab. (Yes, we manually enter every expense, either via SMS or via the spreadsheet. This was a habit we picked up the old YNAB. We could automate this to some extent, but the discipline of having to do something when we spend money has been beneficial).
- I get a confirmation text. My wife gets a text saying "Greg spent $13 on Chipotle. We have $132 left in the lunch category this month."
- Texting "report" to the number kicks back a text with each category and the amount remaining this month.
It's an imperfect system. Some small dollar stuff gets missed. But it's super flexible for reporting since its just a spreadsheet. Because I built it, I actually use it. The confirmation texts have instilled a bit of accountability between the two of us and also serve as a nice reminder during the day of what the other person is doing. ("Hey! Thanks for logging your lunch. How was it?")
Been meaning to write a blog post about it for a while. Will do so if there's interest.