While the mobile app ecosystem flourishes, getting lost in the crowd of 1.5 million apps is more likely than ever before. And most apps actually do get lost, as most of the discovery happens in the top 25 charts. Thus, not surprisingly, most developers refer to the App Store as the top 1 percent economy.

To get into the top 25 list in the U.S., you either need a huge marketing budget or an app that's extremely viral. However, that kind of virility only works with some categories of apps. As download velocity is the main driver for rankings in iOS and a significant part of Google Play listings, a better way to approach this for many indie and bootstrapped developers is to shift focus on regional markets. For example, to get to top 25 in Japan, you only need about 40 percent of total downloads compared to what you'd need in the U.S.

And once you hit the top 25, you can pretty much expect your download rates to skyrocket. The question is, which market should you go for? That depends on who your ideal users are, but in general it's best to stay in culturally similar markets.

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1. Horizontal and vertical distribution

Because we live in a globalized world, things that are popular spread across borders fast. So we want to make it as easy as possible. Distributing an app across the U.S., Australia and Canada makes a lot of sense, because of the minimal language and cultural barriers. An alternative way to approach growth is the so-called horizontal distribution strategy. Instead of climbing up in the ranks, some developers choose to focus on being everywhere.

By creating different versions of their app, they can rank in multiple categories. For example, in addition to its core app, Udemy -- a platform for online learning -- created several different apps for each of their courses. So when you look for programming apps, you will find its programming course. When you look for business apps, you will find one of its business courses, etc.

The downside to this approach is that you lose a little bit of ranking for each of the apps, but on the other hand, you make up for it with your presence across the App Store's ecosystem.

2. App bundling

A very related strategy and something that's only available since the last update is taking advantage of app bundling. Apple basically allows developers to include their apps in up to three bundles of 10 different apps.

There are few potential advantages here. Firstly, bundles are featured in the separate section of the featured apps page, making them much easier to be found. Then there's revenue potential. Bundled apps are often a better value deal which makes them more appealing to at least a certain demographic.

The question here is, if someone downloads your app bundled with nine other apps, how likely are they to actually use it? The way I view it is it may and may not matter. If you can give your app a boost big enough to rank higher, you will reach more users and, as a result, more will adopt.

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3. Retention

So that raises another question. What about retention? The answer is, it's much harder than the user acquisition. In fact, retention makes user acquisition look like a piece of cake.

Mobile analytics companies like Flurry and Apptentive report that you can expect to retain less than 5 percent of users over the course of first 12 months. In fact, most apps are deleted only after used once. That's not surprising as most people only use about 10 to 20 apps on a regular basis -- but they download much more.

Retention has a lot to do with designing a great onboarding process and user engagement. Thinkers like Nir Eyal have done some amazing work on that topic. However, the right place to start is just making a product that users love.

That, of course, sounds like just another startup cliché. What few entrepreneurs get right is understanding that building a great product starts with a focus on a narrow demographic. If you can find a particular customer group and get a thorough understanding of their needs, ultimately you'll be able to translate that knowledge into your product design. There's a reason few of the successful apps have launched in the mainstream market. Facebook first started on Harvard, Instagram focused on travelers and foodies, Uber launched in San Francisco, etc.

Such approach, of course, is the complete opposite of going for quantity and trying to get your app in front of everyone. However, the potential results are not that different. Small communities with high density provide a huge potential for a good product to spread virally in that market. And viral growth means download velocity, which is the ultimate metric to reach the top of the list.

But even that doesn't happen organically. What some of the fastest growing apps did extremely well compared to the rest is that made it easy for viral growth to happen. Apps like Duolingo or QuizUp motivate their users to brag about the results on social media, and Instagram famously achieve a phenomenal growth thanks to the cross-posting feature.

Whichever way you choose to go, knowing your users is the critical thing. Without that knowledge, it's very difficult to create an excellent product. And without a great product, it's practically impossible to retain users -- no matter how smart or creative your marketing is.

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