I am working on a project to build an AI-powered family budget mobile application.
The app will track income and expenses, categorize transactions, analyze spending
patterns, and predict future expenses.

My current planned technology stack is as follows.
Frontend: Flutter or React Native
Backend: Node.js or FastAPI
Database: MongoDB
Machine Learning: Python-based models for expense prediction

I am specifically looking for recommendations on the following areas.
The best machine learning libraries or frameworks for time-series expense prediction.
Tools or frameworks for deploying trained machine learning models to mobile applications, such as TensorFlow Lite or ONNX.
Any proven tooling choices that are commonly used for financial analysis or personal finance use cases.

I am primarily interested in tools that are production-ready, scalable, and well-supported by the community or industry.
I would appreciate suggestions based on real-world experience and practical implementations.