Messaging apps can generate good income for developers, but the ways they generate it vary:

a paid subscription is a dubious option, since most of the competitors' messengers are free;

showing ads is the most common way to monetize any application, but the main thing is not to overdo it, as intrusive ads will only scare away users;

paid functionality - you can arrange the purchase of additional features, such as paid stickers, games or advanced settings;

working with sponsors is the most pleasant option for users, with this approach they can receive certain bonuses for performing any actions in the application from advertisers.

The choice of a monetization strategy is based primarily on the number of users, the popularity of the messenger and other criteria.

What problems might a developer of an application like WhatsApp face?

Every new instant messaging application inevitably faces hurdles when it enters the market.
How to attract new users and keep their number. The application should meet the needs of users as much as possible, be flexible and adaptable to the requirements of customers. It is also important to improve, adequately perceiving the comments and criticism of users, release updates, fix bugs and stimulate the growth of the number of users with new "goodies".
How to ensure security when entering personal data and exchanging messages. It is optimal to develop your own encryption method based on reliable technology. You can use blockchain or use Open Whisper Systems like WhatsApp.

How to meet the growing demands of users. So that the application not only allows you to communicate, you can use it to launch other functions that are unusual for this type of program - for example, payments, as is done in WeChat, games, or the ability to independently create chat bots for various purposes.

In any case, in order to solve all these problems, the developer must listen carefully to the opinions of users, monitor their activity, handle buggies and introduce new technologies and features.

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