Based on my experience, and the answer to this post, there seems to be a delay on the availability of device property tags such as ua_locale_language. Is this indeed true, and if so what is the reason for it?
We localize all our push notifications, and rely on device tags, specifically ua_locale_language and ua_locale_country to schedule localized payloads to the proper audiences.
We expect to be able to send push notifications to a user as soon as the app is installed, but with the delay that ends up not being the case.
Most Device Property tags are available the day after the device makes the registration call with updated device information. This includes the ua_locale_language tag.
Updating Device Property information once per day reduces the load on our system. You should be able to send localized notifications within 24 hours of the first open of the app.
Please let me know if you have any other questions or concerns.
Urban Airship Technical Support
Is there another way to localize push content besides sending separate pushes, each targeting a specific ua_locale_language?
I've been trying a workaround, but I'm a little stuck. I'm setting a tag on the named user with their current language/country (last write wins, obviously), and I want to target messages based on that tag and devices that dot not have a ua_locale_language tag. I could easily do this if the ua_locale_language tag was set to Unknown initially, but the tag doesn't exist at all until that first batch update.
Any ideas? Is it possible to select an audience based on a tag not existing?
I've been thinking about this again. Would it be unreasonable to request a small enhancement? If the users ua_locale_language could be set to the "Unknown" value mentioned in the documentation until that first batch update runs, that would allow us to target those new devices with a fallback language.
Is that something you could bring up to someone? I'm not sure what the proper channels for such a request would be. I think this would be very helpful to anyone working with a localized application.