Self-confessed app nerd Adrienne Gauldie manages UK client accounts for Trademob, the data-driven app marketing platform, and has three years' experience working within the mobile app industry.

While a considerable amount of effort is expended on acquiring users, that is only half of the battle in today's freemium-dominated app market.

An even bigger challenge for many developers is user retention and monetisation.

Before knowing how to retain users, it first must be understood what defines a heavy user for you.

In general, they are defined as those who open an app ten or more times.

These heavy users often become whales – a term taken from the casino industry to describe gamblers who wager large sums of money – a group that makes up around 2-5 percent of a gaming app's user base and are the ones who drive revenue by making in-app purchases (IAP).

By working on your user retention strategy, you can increase the 'heaviness' and longevity of your users, and ultimately monetise a higher number of them.

Successful app marketing for games means identifying where these whales come from and doing all the right things to attract more of them, but of course, it doesn't stop there.

Once you've acquired users for your app, it's important to do all that you can to maximise your retention rates and your users' lifetime value (LTV).

Besides the tracking and optimisation of your marketing campaigns to bring in new, valuable users, what can you do to maximise your users' engagement and stickiness?

Build something great

Possibly the most obvious way to retain users is by creating an addictive game that's agreeably challenging, but not so hard as to impede progress.

Accessible, but not easy, in other words.

It's important to give consideration to user retention during the development phase of your app. By creating effective in-game triggers, you can keep your users logging in and engaging in longer gaming sessions.

Simple mechanics such as paying out daily rewards for opening the app can have a significant impact on user retention.

Madfinger's Dead Trigger, for instance, rewards users with virtual currency and casino chips that can be used in a slot machine just for logging in each day. Additionally, bonus daily quests are presented to give users the chance to earn extra cash and experience points.

Look at your heavy users' actions in detail

We know the importance of tracking mobile ad campaigns in order to understand your users' journeys, from their initial click on an advert to their subsequent download and in-app conversions, such as purchasing tokens.

But we can analyse the data more carefully, for instance by looking for earlier micro conversions, such as registrations or level completions, which could be used to predict whether a user will become a whale or not.

Use a good-sized set of data from your tracking reports – for example >100 downloads – and take a look at each user's journey for the two months following the install date.

What correlations can you find between micro conversions, usage and LTV? Identify ways to encourage those relevant micro conversions, for example with push notifications.

Optimise for maximum user engagement

Once you've tracked and analysed your data, it's time to find your advertising 'sweet spot' and then target your prime audience from now on.

Look to optimise your marketing campaigns with the end goal of maximising the early micro conversions that lead to multiple subsequent in-app conversions and high LTV.

Go back to the start of the user journey for each of your whales. When and where did their first click on your ad take place? Which publisher, ad network, time, date and banner settings were used?

Look at the campaign parameters behind the download and replicate these in future ad campaigns, to target the right kinds of users, in the right place at the right time.

Push notifications

Tailored push notifications are a good way to remind a user to take action, as long as they're well-timed, helpful and don't feel like spam.

Highlighting incentives and rewards users will receive when they register or complete the next level could be a good way to keep them glued. Providing benefits to your users will encourage them to re-open and re-interact with your game.

Push notifications are a great way to boost your daily active users (DAU) and monthly active users (MAU), which are particularly important figures when it comes to monetising an app via advertising.

Mobile retargeting

What about when users have disabled push notifications?

Through retargeting you can show ads to users who have already downloaded your app but didn't yet complete your pre-defined relevant micro conversions or any in-app purchases.

There isn't much collective experience of mobile retargeting to tell us about its effectiveness yet, but it's something we expect to grow, in terms of possibility and successful application, this year.

Audience targeting

Another way of homing in on valuable users that's set to get big this year is audience targeting.

By defining the demographic information of your target audience, for example, age, gender, location and education, and targeting your ads towards this group of users.

But broadly speaking, by defining what makes a heavy user and ascertaining how you can predict high LTV from early micro conversions, it is possible to optimise your ad campaigns in order to maximise acquisition of these valuable users and encourage existing users to re-engage with your app time and time again.

Tailor-made push notifications, retargeting and audience targeting can and should be used to complement your traditional ad campaigns.
To find out more about Trademob, and the services it offers, take a look at the company's website. For more from Adrienne, follow her on Twitter.