Depending on the industry and the app type Id say just reach out to anyone you know or have worked with that will benefit from your product.
Giving an introductory offer for your app is also a great way to get people to try it out.
For earlier products we built, it was always through an outbound sales call or LinkedIn Outreach. But for the first time, we tried to go with Channel Partners like HubSpot and Shopify and it has worked wonders.
Your goal for the first 10, should be to get customers that provide you feedback along with (obviously) money. With channel partners, you can get a greater influx of customers, out of which 25% will surely give you active feedback.
Everything is difficult at the beginning. I think as long as I stick to my plan, I insist on investing 5 hours a day to promote the product
1. Write high-quality blog posts
2. Insist on looking for high-quality external chains of products
3. Find all platforms where products can be listed
4. Take the trouble to obtain feedback from users and optimize the logic and problems of the product
5. Don't give up the above four points easily
This is what I’m doing now, and it’s my own plan
We got our first client through LinkedIn Content, they reached out to see what we're building and how we can help and we closed the deal rather quickly
Our first 4 clients: 2 LinkedIn 2 Personal Connections