android project idea question

Here my first android project idea.

I want to be able to scan coupons into my nexus 6 phone and then at checkout scan phone and it will use all coupons that are eligible?I thought it a good idea but i not sure where to start?

I want to know from you developers what you think about this?Will i need a bar code scanner for my app to work?

I’d not consider using a scanner for this… Just store the raw image of the coupon’s bar code… then you don’t have to re-render the bar-code at checkout.
It could be a simple little app that associates an image (barcode) with a label (coupon name and price) and when you’re at the checkout you could call up the images.

The issue I’d see with this would be store adoption and acceptance. Would the local grocery store or what have you accept scanned coupons?
I’d also consider your market. Would you make money off this? Your audience would be people who want to save money would they pay for your app, given at best it’s a way to organize images?

Where to start would be to grab the sample app in android studios that helps you interact with the camera.

How you might pivot the application if you realize that your market are people who don’t like to depart with their money… An app that helps you organize your images. That I can see bringing in cash.

All IMHO though…