More than 1,000 WatchKit applications have already been available on the App Store along with the release of the Apple Watch on Friday, but Apple will reportedly reject app submissions and updates that support rivals like the Pebble smartwatch.

The developer of SeaNav U.S. for iPhone shared on the Pebble's developer discussion thread that an update for the app has been rejected by Apple since the application and its description "declare support for the Pebble Smartwatch," reports 9to5Mac.

The same report explained that Apple made mention of Rule 3.1 which states that applications naming competing mobile platforms in their description will be rejected. Below is the detailed rule as mentioned by 9to5Mac.

"3.1 - Apps or metadata that mentions the name of any other mobile platform will be rejected

3.1 Details

We noticed that your app or its metadata contains irrelevant platform information in the app. Providing future platform compatibility plans, or other platform references, is not appropriate for the App Store."

In defending the application, the developer said that the app has been on the App Store for about two years now and it did not have any issues until the Apple Watch was announced. The application's update also reportedly does not have any related change on the Pebble smartwatch support.

A Cult of Mac writeup shared Apple's message to the app developer which read: "We noticed that your app or its metadata contains irrelevant platform information in the app. Providing future platform compatibility plans, or other platform references, is not appropriate for the App Store. Specifically, your app and app description declare support for the Pebble Smartwatch."

According to the same report, Apple has long been rejecting iOS apps mentioning rival platforms like Android or Windows Phone, but it noted that this is the first time it had issues with apps mentioning Pebble.

To be able to resolve the issue, Apple reportedly suggests that th developer remove all mentions of Pebble from the description of the app and its metadata.

"But it seems almost impossible to do the same with the official Pebble app, which is required to use a Pebble with your iPhone," added Cult of Mac in raising a valid concern.

It added that it could also just be an error by Apple. Cult of Mac said they have already contacted the company to ask for clarification on the rule for Pebble, though an official response has not yet been received.

This was also the same conclusion of 9to5Mac, saying that the incident could just be an isolated one especially with the release of the Apple Watch. It added that this could be reversed just like other App Store rejections experienced by other app developers since the Pebble app has not yet raised a concern about it being rejected by Apple.