Google appears to be having more issues with Android Wear 2.0. The updated smartwatch operating system was originally expected to release at the end of 2016 but was delayed until this year. Following the official launch last month, Google has now admitted the wider rollout for older Android Wear devices is being pushed back.

The reason for the delay is an undisclosed bug that was discovered during the final testing phase of Android 2.0. No specifics have been released, but it must have been quite serious if the firm decided to delay the release.

When Google officially launched Android 2.0 on February 8, it announced that the first watches to come with the OS would be LG’s Watch Style and Watch Sport, both of which were designed in collaboration with Google. At the time, the company said the 2.0 update would be rolling out to older devices “in the coming weeks.”

In addition to announcing the delay, Google said it was now rolling out Android 2.0 to three newer smartwatches: The Fossil Q Founder, Casio Smart Outdoor Watch WSD-F10, and Tag Heuer Connected. It should arrive on these devices by April 4 at the latest.

"For other devices, the update is currently being delayed due to a bug found in final testing. We will push the update to the remaining devices as soon as the issue is resolved," a spokesperson said in a statement.

9to5Google has a full list of watches that will eventually get the Android Wear 2.0 update, which includes the ZenWatch and Moto 360.