Over-the-air software development kits

What is OTA?

The term "OTA" stands for "over-the-air". The Lokalise OTA service enables your users to get the latest translations on their mobile applications without you needing to submit a new version to be approved by either the Apple or Google app stores.


Lokalise OTA SDK

In this section you'll find technical details covering how to get started with Lokalise OTA SDK.

A simple explanation

Over-the-air localization is a lightweight way to instantly update the content in your apps. It’s particularly useful for fixing typos, finishing translations on the fly, and adding languages.

Imagine the following scenario: You’ve just released a new mobile app version with a new feature and a batch of new translations. The app is approved and users can download it from the app stores. However, you understand that one of the translations contains a mistake — it’s not crucial but still something that should be fixed as soon as possible.

Of course, you could release a new version and upload it to the stores but it will probably take a while to get your app reviewed. Instead, you can fix the faulty translation using the Lokalise web editor, generate an over-the-air bundle (an archive with the updated translations), and distribute this bundle to the end users. The bundle will be downloaded automatically when the app is loaded and the new translation will be displayed instead of the incorrect one.

This significantly cuts down the amount of time and manual work involved, and only requires the initial installation of an over-the-air (OTA) software development kit (SDK) in the mobile app. Currently, we provide three official SDKs: for Android, iOS, and Flutter. We also provide a public OTA API that you can employ to build a custom SDK.

How does it work?

The idea is quite simple. Your mobile application should include a Lokalise OTA SDK that does the heavy lifting. When the application is booted on the user's device, our SDK will automatically connect to the Lokalise over-the-air service and ask if there are any updates available on Lokalise. If updates are found, the corresponding translations will be downloaded and displayed to the user instead of the local ones.

Please note that the OTA bundle does not (and normally should not) contain all the translations for your app: it includes only the translations modified since the last app release. This way you can ensure that the bundle is slim and that downloading it does not take too much time thus affecting overall performance.


OTA workflow

What about pricing?

The OTA service can be used on every subscription plan (the only exception is the Free plan; you can still use OTA on Trial though). The pricing model is based on gigabytes of consumed data per month. There are three main factors:

  • Number of app users
  • Bundle sizes in gigabytes that your users are downloading
  • Number of monthly bundle releases

In other words, the bigger your bundles are and the more often users download them, the more you’ll need to pay. This, in turn, means that having a slim bundle is very important.

For every subscription plan, we provide a limit on gigabytes per month, but you can go over this limit if needed. Read more details on OTA pricing here.

Further reading