I have created over 200 mobile apps for Android, so I think I can help on how to prepare a budget and have some thoughts on investors.

First, the investor. I prefer not to use an investor, I took our initial $3,000 which has personally made me over a million dollars in the app space. However, I think the experience for you to meet one will have a lot of good learnings, just be very prepared.

Preparing a budget. So create a spec document, be clear on your app and the vision (this will help or should have been done for an investor). Then reach out to a bunch of outsourcing companies (upwork, PeoplePerHour etc...) and get a good understanding of the cost to develop your android app. You will be shocked to see how the price difference is depending on where you get it developed. This will give you an idea on the cost.

Then once you know the budget and if it is high, go with an investor, if it is not then dont. My first app, I got quotes for $300 and $10,000. I spent $300 by a buy working on the side of his day job plus the work I did myself to create the app and later sold it.

The $3,000 to start was spent on $2400 went to training/mentors and $300 to set up a company. Good mentoring and training matters from experienced professional.

Cheers,
Mukul

If I can help, call me