I encountered problems reading a 220 byte string on iOS. It worked fine on Android, and after debugging I found out that BlueZ is returning some pParameters in the Method callback, mainly "offset" appeared.

This is just a simple method to look for the "offset" parameter and also a piece of example code of it being applied. You should only need to call getOffsetFromParameters() if the data being returned (either byte array or c-string) can be pretty large. afaik iOS is the only OS that actually breaks reads up like this (at 184 byte intervals), everything else just uses the HCI automatic packet chunking (even my Galaxy S6 worked on data over 4Kbs).