I was sending .5 mb size dictionary through iPhone to watch os2, however every time it is giving message reply failed. It is working correctly in watchos1. There are 700 objects in that dictionary. Please help.
The payload size is dependent on how you send the content from the phone to the watch. You may want to consider breaking your dictionary into smaller chunks, (smaller than 65KB), or write the dictionary to a file you can then send using WCSession's transferFile:metadata method.
For more info, see this question and answer, and take a look at the docs for WCSession. The file size limits aren't documented, and may change in the future.