Personally, I think you should be focusing heavily on your current users that are loyal to your brand currently and worry less on trying to buy users and get more brand awareness. To be frank you should be letting your strongest customers do all the promotion for you organically. "K-factor" This is how why you see businesses that get super big out of nowhere with practically nil paid marketing budgets.

One of the differences of the David v Goliath mentality is companies believe they need to take on Goliath. The truth is, however, your company can operate at a high level by offering your customers the best services, prices, quality, etc that you can and be focused completely on the customer experience.

The problem is by trying to compete with your competitors you are wasting all your money/time trying to beat or get market share vs. building a high quality business.

Focus on acquiring the customers you can through traditional paid, organic channels however stop focusing on trying to compete for market share. Focus on your product/business and ensuring that you have high retention %/ repeat users/payers, etc.

I worked at Lyft and to be honest we had that mentality vs. Uber who are essentially monsters compared to us. "Oh how will Lyft ever make a dent in Uber's market share" They have more money, resources, etc. The difference, however, was the customer experience with Lyft. Lyft, overall, is friendlier, and a better experience IMHO. Thus, you now see Lyft making major strides in market share in the ride-sharing economy.

At the end of the day, IMHO eventually the customer experience, product etc. will help you organically eat into enough market share.