With the increase in available products and services, unplanned spending has become an indispensable part of everyday life. Planning finances and savings for the future has become a struggle for many. Numerous methods that can be used to track expenses, both modern and traditional, are available. Mobile applications are becoming increasingly popular for tracking and planning personal finances, over traditional approaches like paper and spreadsheets, especially among the younger generation. This paper proposes the implementation of the expense tracking application, providing functionalities that will accelerate input of expenses, such as adding transactions with receipt scanning and automatic categorization. Users can easily add transactions, through an intuitive user interface, by scanning the QR code on the receipt (issued in the Republic of Serbia) or manually. The bill data and items are fetched from the Tax Administration office website. Expenses are automatically categorized and summarized based on bill items using the Large Language Models (LLMs) with minimal user engagement. Classifying costs based on bill items leads to greater precision compared to classifying based on location which is used by most other applications. The charts show the amount of money spent across categories on a monthly and annual level. It is possible to set a limit for each month and observe whether the limit is exceeded over time to achieve more sustainable spending.