Apple has informed the developers that all Apple Watch apps will be required to use the native SDK starting June 1. The native SDK is what allows the Apple Watch apps to run natively on the Watch itself, unlike the original watchOS SDK that would run the apps on the phone and then stream it to the watch over Bluetooth, which was the main reason for the slow performance of third party apps on the Apple Watch. With watchOS 2.0, Apple announced native apps but the older SDK and apps were still supported. Starting June 1, that will no longer be the case. This should finally force...
Source: http://www.gsmarena.com/all_apple_watch_apps_required_to_use_native_sdk_from_june_1-news-17933.php
