Today Apple has released iOS 12.1.2 for supported devices. As its version number implies, this is a minor update, weighing in at 100MB. It doesn't bring any new features to the table, but it might be quite important for you if you own an iPhone XS, iPhone XS Max, or iPhone XR. That's because it fixes bugs with eSIM activation on Apple's 2018 devices. eSIM support was recently enabled for the trio of handsets, but apparently it hasn't all been smooth sailing. Hopefully no more issues pertaining to this function will arise from this point on. iOS 12.1.2 also addresses an issue that...
Source: https://www.gsmarena.com/ios_1212_is_out_to_fix_esimrelated_issues-news-34744.php