So in exchange for some traffic they want

- their branding on your app

- you to pay all the bills / labor / support / etc

- 50% of the revenue

The revenue's the real killer, them funneling some traffic to you is almost certainly not worth 50% of your revenue, especially when they're just sending a pair of eyes (quality eyes perhaps, but still) that you have to effectively monetize.

Adwords and Facebook ads can also do that and they won't cost you anywhere near as much.