As it turns out, however, Telegram no longer works on CarPlay after the most recent iOS update published on December 23, though right now, it’s still not clear if this is an intentional change or just something caused by a bug.
The December 23 Telegram update brought the app to version 7.3, and it introduced voice chats in groups, sticker outlines, new Siri capabilities, and others. For CarPlay users, however, the Telegram support just came down to notifications being displayed on the head unit, and Siri able to read the received messages.
The dev team hasn’t shared any information regarding their CarPlay plans, and the release notes shipping with the latest version don’t include any details as to whether the app would give up on support for the car platform or not.
At this point, there’s not much users can do in order to restore Telegram on CarPlay if they already installed the latest version of the app. Given Apple’s walled garden, downgrading to an earlier version of an app is a huge pain in the neck for iPhone users, so if you’re not already on Telegram 7.3, you’d better delay the update if the CarPlay support is something you are using regularly.
Telegram typically releases new updates once per month, so if this is indeed a bug, expect a patch to resolve it at some point in January. But of course, you’d better not hold your breath for a Telegram fix in this regard, as the company is yet to officially acknowledge this problem.