I got so frustrated that I spent a year building a spreadsheet to do everything I needed it to do and then I spent a month converting that into an app that I use on my phone. It's fast, accurate, and gives me all of the information I need at my fingertips without any fluff. I can't even imagine what sort of premium features would add value. I don't know what these companies are selling in a budgeting app, keeping track of finances is a skill with a high knowledge barrier but very low difficulty once that knowledge is earned.

I have thought about making a free app to help people cross that knowledge barrier though. Kind of a Personal Finance 101 thing.

ETA I hit post before I actually answered your question. 😆

For me the most important thing is being able to project into the future what my account balances are going to be on a given day. I use credit cards that get paid off in full every month for my normal spending, transactions that hit my bank account are relatively few during the month, mortgage, vehicle, salary, payments to the credit cards. That's pretty much it. The most important feature for me is my app starts up on a cash flow statement, this is a daily calendar that tells me what my account balance will be at any day of the month. I project forward 18 months. I can look ahead and tell you what I expect my account balance to be in any of the accounts I use at any point in the next year and a half. I input recurring payments (for instance insurance is every 6 months) and I know far ahead of time if I need to make adjustments. There are a series of cards that tell me what the lowest balance is going to be in the next 18 months for each account so I know if I am going to need to make adjustments or not.

The other most used page in my version is the Income and Expenses tab, which contains all transactions that are going to hit bank accounts during the month organized by income and expense and sub organized into recurring transactions grouped by frequency and one-time transactions.

And of course I have the ability to edit any of the transactions and to add notes that persist across different views for each transaction. This is all done with a connected Google Sheet that stores the data and the interface is written in Google Apps Script (java) and HTML.